[CIVIS-9349] assign the single running test suite for a test if none found by test suite name

[anmarchenko]

What does this PR do?
Makes test suite assignment more robust by assigning the single runinng test suite to a test when no test suite found by name.

Motivation
There are cases where minitest test suite names fluctuate from test to test because of using external libraries like shoulda-context and/or activesupport concerns. While #134 fixed most of these cases there are still a very small chance of some test cases (inside anonymous classes?) that are skipped because of missing test suite id.

Thankfully, if minitest executes tests sequentially, there should be only one test suite running at a time: we can use it to assign "lost tests" to whichever test suite that is currently running.

How to test the change?
Unit tests are provided

[codecov-commenter]

Codecov Report

Attention: Patch coverage is 95.91837% with 2 lines in your changes are missing coverage. Please review.

Project coverage is 99.06%. Comparing base (301b899) to head (0f74894).

Files	Patch %	Lines
lib/datadog/ci/test_visibility/recorder.rb	81.81%	2 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #139      +/-   ##
==========================================
- Coverage   99.08%   99.06%   -0.03%     
==========================================
  Files         164      164              
  Lines        7239     7288      +49     
  Branches      304      308       +4     
==========================================
+ Hits         7173     7220      +47     
- Misses         66       68       +2     

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