Add utility decorator to log time spent in function calls

[lunkwill42]

Scope and purpose

This adds a utility decorator log_time_spent(), which will log the number of seconds spent in the decorated function. It also applies this to functions that load polldevs config or loads/dumps the Zino state, in order to get a picture of the performance of these functions.

Contributor Checklist

Every pull request should have this checklist filled out, no matter how small it is.
More information about contributing to Zino can be found in the
README.

• Added a changelog fragment for towncrier
  • Purely an internal change.
• Added/amended tests for new/changed code
• Added/changed documentation
  • Well, tests are documentation, right?
• Linted/formatted the code with black, ruff and isort, easiest by using pre-commit
• The first line of the commit message continues the sentence "If applied, this commit will ...", starts with a capital letter, does not end with punctuation and is 50 characters or less long. See https://cbea.ms/git-commit/
• If applicable: Created new issues if this PR does not fix the issue completely/there is further work to be done

[github-actions]

🦙 MegaLinter status: ✅ SUCCESS

Descriptor	Linter	Files	Fixed	Errors	Elapsed time
✅ PYTHON	black	100		0	1.71s
✅ PYTHON	isort	100		0	0.34s
✅ PYTHON	ruff	100		0	0.03s

See detailed report in MegaLinter reports

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[github-actions]

Test results

    3 files      3 suites   1m 17s ⏱️
  514 tests   514 ✅ 0 💤 0 ❌
1 542 runs  1 540 ✅ 2 💤 0 ❌

Results for commit 7367e79.

♻️ This comment has been updated with latest results.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 97.32%. Comparing base (5fb634d) to head (126c493).

Additional details and impacted files

@@            Coverage Diff             @@
##           master     #317      +/-   ##
==========================================
+ Coverage   97.31%   97.32%   +0.01%     
==========================================
  Files          64       64              
  Lines        7888     7910      +22     
==========================================
+ Hits         7676     7698      +22     
  Misses        212      212              

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[sonarcloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarCloud

[johannaengland]

I didn't do any change to the code, only fixed a typo in the commit message