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).
⚠️ Report is 27 commits behind head on master.

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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