docs: Fix typo in CONTRIBUTING.md

[Divika-23]

Fixed a minor typo in CONTRIBUTING.md.

Changed:
"There are a just a few small guidelines you need to follow."
to
"There are just a few small guidelines you need to follow."

No functional changes were made.

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[gmlewis]

Instead of starting the line with a space, how about start the line with "There are " and remove it from the end of line 3?

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 94.08%. Comparing base (ba35d25) to head (c419509).

Additional details and impacted files

@@           Coverage Diff           @@
##           master    #4052   +/-   ##
=======================================
  Coverage   94.08%   94.08%           
=======================================
  Files         207      207           
  Lines       19217    19217           
=======================================
  Hits        18081    18081           
  Misses        938      938           
  Partials      198      198           

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