python-argcomplete: add test-version.sh for CI

python-argcomplete: add test-version.sh for CI

The three CLI helpers shipped by python3-argcomplete
(activate-global-python-argcomplete, register-python-argcomplete,
python-argcomplete-check-easy-install-script) don't accept a --version
flag and emit no PKG_VERSION string in their usage output. With all
three executables missing the version, the generic CI test stage
fails with "No executables in the package provided version 3.6.3".

Add a test-version.sh that emits a line containing PKG_VERSION so the
framework's "Version check override" passes. The existing test.sh
already exercises the Python module import.

Signed-off-by: Alexandru Ardelean <redacted>