This continues the changes from a576000f (software/html5as: serialize
as json-in-xml, 2022-08-19) to fix a test failure and serialize also
in json-in-xml for the replicate software type.

Minor changes to tests were made, to use assertIn for better messages
in case of assertion failures

after slapos commit cc7f36a0 (component/defaults: use python3 by
default, 2022-08-27) this test accidentally switched to using python3.

using python3 showed an incompatibility:

   File ".nxdtest", line 23, in <module>
     TestCase('transaction',['python', '-m', 'unittest', 'discover', '-s', P(transaction)])
   File ".nxdtest", line 22, in P
     def P(path): return os.path.join(path, '..')
   File "lib/python3.8/posixpath.py", line 90, in join
     genericpath._check_arg_types('join', a, *p)
   File "lib/python3.8/genericpath.py", line 155, in _check_arg_types
     raise TypeError("Can't mix strings and bytes in path components") from None
 TypeError: Can't mix strings and bytes in path components

that we also address here by using universal_newlines to the subprocess

test.cfg becomes the python3 version
a new test-py2.cfg is introduced
test-py3.cfg is removed

cf slapos commit cc7f36a0 (component/defaults: use python3 by default, 2022-08-27)

Change python2 softwares to use python2 explicitly and python3
softwares to use the default, but leave a few softwares (html5as,
html5as-base, fluent-bit, packer, seleniumrunner) using the default
python, as they were using python2 not because they only support python2
but because they don't have strong dependency to the python version
being used.

See merge request nexedi/slapos!1235

https://restic.net/blog/2022-08-25/restic-0.14.0-released/

see nexedi/slapos!1215

See merge request !1234

so we will not forget to update it

See merge request !1233

Remove the "--disable-static" configure option. Fix the warning message: "configure: WARNING: unrecognized option: '--disable-static'".
See merge request !1231

Resolve `@theia/core` subdependency `vscode-uri` to a locally installed patched version, to workaround https://github.com/microsoft/vscode/issues/154048.

This fixes access to Theia through the IPv6 `backend-url`. That issue was discussed in !1204

The patched version of `vscode-uri` is published here: https://github.com/xavth/vscode-uri/tree/fix/ipv6_url_authority

To do this, `yarn.lock` was regenerated, so this also caused a version up to Theia 1.28.0.

See merge request !1227

See merge request nexedi/slapos!1217

Instead of lying in tests and checking for NotReadyYet in the connection
parameteres use promise to assert that generation of KeDiFa URLs is really
ready.

Drop hacks applied in the test, so that it will uncover all missing promises
and corner cases.

bootstrap-script-url and data-to-vm are important features of
enable-http-server and are expected to work correctly, thus cover them
with instance-level testing.

In mean time fix detected issues.

See merge request nexedi/slapos!1222

  The content of inline is a jinja2 template