packer: all ubuntu preseed files are the same

So keep everything in the same file

packer/http/preseed-ubuntu.cfg

@@ -25,3 +25,15 @@ d-i time/zone string CET
 d-i user-setup/allow-password-weak boolean true
 d-i user-setup/encrypt-home boolean false
 tasksel tasksel/first multiselect standard, ubuntu-server
+
+d-i preseed/early_command string                                                                                                                \
+        mkdir -p /usr/lib/post-base-installer.d &&                                                                                              \
+        echo "sed -i -e 's/^in-target.*tasksel.*/#\\0/' /var/lib/dpkg/info/pkgsel.postinst" > /usr/lib/post-base-installer.d/90skip-tasksel &&  \
+        chmod +x /usr/lib/post-base-installer.d/90skip-tasksel
+
+d-i preseed/late_command string                                                   \
+        echo 'Defaults:slapos !requiretty' > /target/etc/sudoers.d/slapos;        \
+        echo 'slapos ALL=(ALL) NOPASSWD: ALL' >> /target/etc/sudoers.d/slapos;    \
+        chmod 440 /target/etc/sudoers.d/slapos ;                                  \
+        ln -sf /dev/null /target/etc/systemd/network/99-default.link;             \
+        in-target update-initramfs -u

packer/http/preseed-ubuntu16.04.cfg

-d-i preseed/include string ../preseed-ubuntu.cfg
-
-d-i preseed/early_command string                                                                                                                \
-        mkdir -p /usr/lib/post-base-installer.d &&                                                                                              \
-        echo "sed -i -e 's/^in-target.*tasksel.*/#\\0/' /var/lib/dpkg/info/pkgsel.postinst" > /usr/lib/post-base-installer.d/90skip-tasksel &&  \
-        chmod +x /usr/lib/post-base-installer.d/90skip-tasksel
-
-d-i preseed/late_command string                                                   \
-        echo 'Defaults:slapos !requiretty' > /target/etc/sudoers.d/slapos;        \
-        echo 'slapos ALL=(ALL) NOPASSWD: ALL' >> /target/etc/sudoers.d/slapos;    \
-        chmod 440 /target/etc/sudoers.d/slapos ;                                  \
-        ln -sf /dev/null /target/etc/systemd/network/99-default.link;             \
-        in-target update-initramfs -u

packer/http/preseed-ubuntu18.04.cfg

-d-i preseed/include string ../preseed-ubuntu.cfg
-
-d-i preseed/early_command string                                                                                                                \
-        mkdir -p /usr/lib/post-base-installer.d &&                                                                                              \
-        echo "sed -i -e 's/^in-target.*tasksel.*/#\\0/' /var/lib/dpkg/info/pkgsel.postinst" > /usr/lib/post-base-installer.d/90skip-tasksel &&  \
-        chmod +x /usr/lib/post-base-installer.d/90skip-tasksel
-
-d-i preseed/late_command string                                                   \
-        echo 'Defaults:slapos !requiretty' > /target/etc/sudoers.d/slapos;        \
-        echo 'slapos ALL=(ALL) NOPASSWD: ALL' >> /target/etc/sudoers.d/slapos;    \
-        chmod 440 /target/etc/sudoers.d/slapos ;                                  \
-        ln -sf /dev/null /target/etc/systemd/network/99-default.link;             \
-        in-target update-initramfs -u

packer/http/preseed-ubuntu20.04.cfg

-d-i preseed/include string ../preseed-ubuntu.cfg
-
-d-i preseed/early_command string                                                                                                                \
-        mkdir -p /usr/lib/post-base-installer.d &&                                                                                              \
-        echo "sed -i -e 's/^in-target.*tasksel.*/#\\0/' /var/lib/dpkg/info/pkgsel.postinst" > /usr/lib/post-base-installer.d/90skip-tasksel &&  \
-        chmod +x /usr/lib/post-base-installer.d/90skip-tasksel
-
-d-i preseed/late_command string                                                   \
-        echo 'Defaults:slapos !requiretty' > /target/etc/sudoers.d/slapos;        \
-        echo 'slapos ALL=(ALL) NOPASSWD: ALL' >> /target/etc/sudoers.d/slapos;    \
-        chmod 440 /target/etc/sudoers.d/slapos ;                                  \
-        ln -sf /dev/null /target/etc/systemd/network/99-default.link;             \
-        in-target update-initramfs -u

packer/ubuntu-16.04-server-amd64.json

@@ -25,7 +25,7 @@
         "passwd/user-password={{user `password`}} ",
         "passwd/username={{user `user`}} ",
         "noapic ",
-        "preseed/url=http://{{ .HTTPIP }}:{{ .HTTPPort }}/preseed-ubuntu16.04.cfg ",
+        "preseed/url=http://{{ .HTTPIP }}:{{ .HTTPPort }}/preseed-ubuntu.cfg ",
         "<enter>"
       ],
       "boot_wait": "3s",

packer/ubuntu-18.04-server-amd64.json

@@ -19,7 +19,7 @@
         "passwd/user-password={{user `password`}} ",
         "passwd/username={{user `user`}} ",
         "noapic ",
-        "preseed/url=http://{{ .HTTPIP }}:{{ .HTTPPort }}/preseed-ubuntu18.04.cfg ",
+        "preseed/url=http://{{ .HTTPIP }}:{{ .HTTPPort }}/preseed-ubuntu.cfg ",
         "-- <enter>"
       ],
       "boot_wait": "2s",

packer/ubuntu-20.04-server-amd64.json

@@ -19,7 +19,7 @@
         "passwd/user-password={{user `password`}} ",
         "passwd/username={{user `user`}} ",
         "noapic ",
-        "preseed/url=http://{{ .HTTPIP }}:{{ .HTTPPort }}/preseed-ubuntu20.04.cfg ",
+        "preseed/url=http://{{ .HTTPIP }}:{{ .HTTPPort }}/preseed-ubuntu.cfg ",
         "-- <enter>"
       ],
       "boot_wait": "2s",