feat: [AH-3247] Add mean time between failures

[VebjornG]

Description

We calculate the mean time between failures (MTBF) of a system based on
the sum of the mean time to failure (MTTF) and mean time to resolution
(MTTRes).

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• Refactor (non-breaking change which improves implementation)
• Performance (non-breaking change which improves performance. Please add associated performance test and results)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Non-functional change (xml comments/documentation/etc)

Contributor Checklist:

• My code follows the code style of this project.
• I have added an example of my new feature and included it in the documentation.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have read the CONTRIBUTING document.
• I have added tests to cover my changes.
• All new and existing tests passed.
• My Pull Request name follows the naming convention fix: <description>, feat: <description>, etc.

Reviewer Checklist for Charts compliant functions:

• The docstrings of the new function follow the contributing guidelines.
• The new function is professionally documented
• The new function and associated scripts are covered by one or more unit tests and code coverage did not decrease.
• The new function is accompanied by an example and it is included in the Gallery of Charts.
• The new function is reviewed in Chromatic. Access the storybook build results url and comment, approve or deny.
• All function inputs, arguments, and outputs have a supported data type and have human readable names.
• No code language is included in the description of the function or parameters (e.g use "polynomial order" instead of "poly_order")

[codecov]

Codecov Report

Attention: Patch coverage is 50.00000% with 5 lines in your changes missing coverage. Please review.

Project coverage is 72.65%. Comparing base (be011bb) to head (9836e4a).
Report is 8 commits behind head on main.

❗ There is a different number of reports uploaded between BASE (be011bb) and HEAD (9836e4a). Click for more details.

HEAD has 9 uploads less than BASE

Flag	BASE (be011bb)	HEAD (9836e4a)
	21	12

Additional details and impacted files

@@             Coverage Diff             @@
##             main     #245       +/-   ##
===========================================
- Coverage   91.27%   72.65%   -18.62%     
===========================================
  Files         106      107        +1     
  Lines        3863     3873       +10     
  Branches      839      840        +1     
===========================================
- Hits         3526     2814      -712     
- Misses        208      928      +720     
- Partials      129      131        +2     

Files	Coverage Δ
indsl/equipment/__init__.py	100.00% <100.00%> (ø)
indsl/equipment/mean_time_between_failures_.py	44.44% <44.44%> (ø)

... and 41 files with indirect coverage changes

[github-actions]

Unit Test Results

   15 files   -     6     15 suites   - 6   22m 27s ⏱️ - 14m 27s
1 117 tests +    3  1 115 ✅ +    1   0 💤 ±0  2 ❌ +2 
9 099 runs   - 6 675  9 081 ✅  - 6 681  12 💤 ±0  6 ❌ +6 

For more details on these failures, see this check.

Results for commit 9836e4a. ± Comparison against base commit be011bb.

♻️ This comment has been updated with latest results.