component/glib: set --with-python to generate scripts with slapos python

glib configure script uses by default python2.7 to substitute in scripts,
but it also supports --with-python argument. Since the scripts support
python2 or python3, we can use the full path of the python used by
buildout. This will sometimes create shebang lines like:

    #!/usr/bin/env /path/to/slapos/python3/bin/python

but this also work fine.

This replaces the following commits:
 - 7581b668 (component/glib: remove bad file bin/gtester-report after compilation, 2020-08-07)
 - 9c47f828 (componnent/gtk-2: Add python2.7 as the dependency of pango, 2022-08-18)

component/glib/buildout.cfg

@@ -25,6 +25,7 @@ configure-options =
   --disable-fam
   --disable-xattr
   --disable-man
+  --with-python=${buildout:executable}
 environment =
   PATH=${gettext:location}/bin:${patch:location}/bin:${perl:location}/bin:${xz-utils:location}/bin:%(PATH)s
   CPPFLAGS=-I${gettext:location}/include -I${zlib:location}/include
@@ -33,7 +34,6 @@ environment =
   LIBFFI_LIBS= -L${libffi:location}/lib -Wl,-rpath=${libffi:location}/lib -lffi
   PCRE_CFLAGS=-I${pcre:location}/include
   PCRE_LIBS=-L${pcre:location}/lib -Wl,-rpath=${pcre:location}/lib -lpcre
-post-install = rm %(location)s/bin/gtester-report
 
 [x86-cygwin-glib]
 patches =

component/gtk-2/buildout.cfg

@@ -14,7 +14,6 @@ extends =
   ../libtool/buildout.cfg
   ../m4/buildout.cfg
   ../perl/buildout.cfg
-  ../python-2.7/buildout.cfg
   ../pkgconfig/buildout.cfg
   ../xorg/buildout.cfg
   ../icu/buildout.cfg
@@ -82,7 +81,7 @@ configure-options =
   --disable-static
   --disable-gtk-doc-html
 environment =
-  PATH=${python2.7:location}/bin:${glib:location}/bin:${freetype:location}/bin:${pkgconfig:location}/bin:${xz-utils:location}/bin:%(PATH)s
+  PATH=${glib:location}/bin:${freetype:location}/bin:${pkgconfig:location}/bin:${xz-utils:location}/bin:%(PATH)s
   PKG_CONFIG_PATH=${:pkg_config_depends}
   CPPFLAGS=-I${bzip2:location}/include -I${zlib:location}/include
   LDFLAGS=-L${bzip2:location}/lib -Wl,-rpath=${bzip2:location}/lib -L${zlib:location}/lib -Wl,-rpath=${zlib:location}/lib -L${harfbuzz:location}/lib -Wl,-rpath=${harfbuzz:location}/lib