fix(api): validate before creating projects based on current subscription

[tushar5526]

Closes #2835
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Changes

Subscription metadata contains the number of projects allowed in a subscription, use that to validate and create project requests.

PS: All the tests are written assuming that the default subscription allows the creation of multiple projects, therefore I had to allow up to the creation of 10 projects in the default subscription for tests. Another way could to be change the default subscription for every failing test that requires the creation of multiple projects.

How did you test this code?

Created a test ORG and tried to create multiple projects via API.

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Codecov Report

Attention: 2 lines in your changes are missing coverage. Please review.

Comparison is base (b0ef013) 95.60% compared to head (89adb29) 95.61%.
Report is 79 commits behind head on main.

❗ Current head 89adb29 differs from pull request most recent head d169e96. Consider uploading reports for the commit d169e96 to get more accurate results

Files	Patch %	Lines
api/integrations/launch_darkly/tasks.py	0.00%	2 Missing ⚠️

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #2869   +/-   ##
=======================================
  Coverage   95.60%   95.61%           
=======================================
  Files        1009     1009           
  Lines       28904    28936   +32     
=======================================
+ Hits        27634    27666   +32     
  Misses       1270     1270           

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[matthewelwell]

Thanks again for this @tushar5526 ! I've added a few (mostly minor) comments but this looks good on the whole.

[matthewelwell]

I've added a couple of minor comments but on the whole, this looks great. Thanks again @tushar5526 .