stack/slapos.cfg: more sort eggs version alphabetically

Using "Sort Lines Ascending" from Theia or `:'<,'>!sort -f` from vim
produce this diff.

stack/slapos.cfg

@@ -182,8 +182,8 @@ ipaddress = 1.0.23
 itsdangerous = 0.24
 Jinja2 = 2.11.3
 jsonschema = 3.0.2:whl
-lockfile = 0.12.2:whl
 lock-file = 2.0
+lockfile = 0.12.2:whl
 lxml = 4.9.1
 MarkupSafe = 2.0.1
 meld3 = 1.0.2
@@ -204,10 +204,10 @@ pluggy = 0.13.1:whl
 prettytable = 0.7.2
 psutil = 5.8.0
 py = 1.11.0:whl
+py-mld = 1.0.3
 pyasn1 = 0.4.5
 pycparser = 2.20
 pycurl = 7.43.0
-py-mld = 1.0.3
 PyNaCl = 1.3.0
 pyOpenSSL = 19.1.0
 pyparsing = 3.0.9:whl