Add tanzukubernetescluster tag to clusterclass datasource tests

[ramya-bangera]

1. What this PR does / why we need it:
   Add tanzukubernetescluster tag to clusterclass datasource tests to ensure that these tests are triggered while we run the tanzukubernetescluster tests in automation as both of them share the same environment requirements.

2. Which issue(s) this PR fixes

    (optional, in `fixes #<issue number>` format, will close the issue(s) when PR gets merged):
   
    Fixes #
   

3. Additional information

4. Special notes for your reviewer

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Comparison is base (b4c3cb5) 25.40% compared to head (9ee214b) 25.40%.

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #376   +/-   ##
=======================================
  Coverage   25.40%   25.40%           
=======================================
  Files         195      195           
  Lines       16784    16784           
=======================================
  Hits         4264     4264           
  Misses      12302    12302           
  Partials      218      218           

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[github-actions]

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