Improve error message for overloaded declaration

[PratikDhanave]

Closes #520

Description

---

• Targeted PR against master branch
• Linked to Github issue with discussion and accepted design OR link to spec that describes this work
• Code follows the standards mentioned here
• Updated relevant documentation
• Re-reviewed Files changed in the Github PR explorer
• Added appropriate labels

[turbolent]

Thank you for the contribution!

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[PratikDhanave]

hi @turbolent @SupunS I have update pr please review

[PratikDhanave]

hi @turbolent @SupunS I have update pr please review

hi @turbolent thank you for review I have resolved the comments

[codecov]

Codecov Report

Merging #2738 (9132dfa) into master (016525d) will increase coverage by 0.07%.
Report is 35 commits behind head on master.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##           master    #2738      +/-   ##
==========================================
+ Coverage   79.11%   79.18%   +0.07%     
==========================================
  Files         333      333              
  Lines       78194    78536     +342     
==========================================
+ Hits        61861    62192     +331     
- Misses      14041    14043       +2     
- Partials     2292     2301       +9     

Flag	Coverage Δ
unittests	79.18% <100.00%> (+0.07%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Files Changed	Coverage Δ
runtime/sema/check_composite_declaration.go	95.79% <100.00%> (+0.02%)	⬆️

... and 11 files with indirect coverage changes

[turbolent]

Thank you!