prefer using importlib.metadata over the deprecated pkg_resources in det_pypkg_version + switch container tests to rockylinux 8.10

[boegel]

fixes #4903

[jfgrimm]

@boegel any idea why the container tests are failing?

[lexming]

LGTM

[branfosj]

@boegel any idea why the container tests are failing?

I can reproduce locally...

Last part of the EB log...

== building...
  >> running shell command:
        make  -j 12
        [started at: 2025-05-28 19:04:28]
        [working dir: /scratch/build/M4/1.4.19/system-system/m4-1.4.19]
        [output and state saved to /scratch/tmp/eb-lmgdsutm/run-shell-cmd-output/make-d342nyst]
== ... (took 1 secs)
== FAILED: Installation ended unsuccessfully: shell command 'make ...' failed with exit code 2 in build step for M4-1.4.19.eb (took 40 secs)
== Results of the build can be found in the log file(s) /scratch/tmp/eb-lmgdsutm/easybuild-M4-1.4.19-20250528.190349.UGasO.log
== Summary:
   * [SUCCESS] zlib/1.2.11
   * [FAILED]  M4/1.4.19
   * [SKIPPED] Bison/3.8.2
   * [SKIPPED] flex/2.6.4
   * [SKIPPED] binutils/2.37
   * [SKIPPED] bzip2/1.0.8

[branfosj]

Broken by the changes in easybuilders/easybuild-easyconfigs#22798 with @boegel's comment being the reason. The container tests use Centos 7.

See #4906 for switching to a newer container for the container tests.

[branfosj]

See #4906 for switching to a newer container for the container tests.

And both this PR and #4906 will need to be in the same PR to avoid both of the sets of test failures that these two PRs fix.

[branfosj]

@boegel boegel#55 adds the changes from #4906 to this PR to solve the two test suite issues.

[boegel]

@boegel boegel#55 adds the changes from #4906 to this PR to solve the two test suite issues.

Merged, thanks for the help with figuring out this one @branfosj!