Fix flaky test_mount_unmount_zfs_file_system()

[pem70]

What It Does
Fixes #383

How to Test
Run test_mount_unmount_zfs_file_system() and make it fail before unmounting. The created file system should still be unmounted and deleted.

Review Checklist
I certify that I have:

• tested my changes
• added/updated automated tests
• updated the changelog
• followed the contribution guidelines

Additional Comments

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 82.13%. Comparing base (14a6814) to head (c3e398a).
⚠️ Report is 5 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #384   +/-   ##
=======================================
  Coverage   82.13%   82.13%           
=======================================
  Files          49       49           
  Lines        2916     2916           
=======================================
  Hits         2395     2395           
  Misses        521      521           

Flag	Coverage Δ
unittests	82.13% <ø> (ø)

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[zFernand0]

Shifting things a bit in the GH project. However, this is still in my radar to review 🙏

[zFernand0]

LGTM! 😋

[github-actions]

Release succeeded for the main branch. 🎉

The following packages have been published:

• pypi: zowe_core_for_zowe_sdk-1.0.0.dev25
• pypi: zowe_python_sdk_bundle-1.0.0.dev25
• pypi: zowe_workflows_for_zowe_sdk-1.0.0.dev25
• pypi: zowe_zos_console_for_zowe_sdk-1.0.0.dev25
• pypi: zowe_zos_files_for_zowe_sdk-1.0.0.dev25
• pypi: zowe_zos_jobs_for_zowe_sdk-1.0.0.dev25
• pypi: zowe_zos_tso_for_zowe_sdk-1.0.0.dev25
• pypi: zowe_zosmf_for_zowe_sdk-1.0.0.dev25

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