feat: resend invite api for group role

[ranjitkshah]

reqd for #fossasia/open-event-frontend#7730

Checklist

• I have read the Contribution & Best practices Guide and my PR follows them.
• My branch is up-to-date with the Upstream development branch.
• The unit tests pass locally with my changes
• I have added tests that prove my fix is effective or that my feature works
• I have added necessary documentation (if appropriate)

• All the functions created/modified in this PR contain relevant docstrings.

[codecov]

Codecov Report

Merging #8184 (9bc4cd0) into development (19fcb86) will increase coverage by 0.00%.
The diff coverage is 75.00%.

@@             Coverage Diff              @@
##           development    #8184   +/-   ##
============================================
  Coverage        65.74%   65.75%           
============================================
  Files              305      306    +1     
  Lines            15811    15823   +12     
============================================
+ Hits             10395    10404    +9     
- Misses            5416     5419    +3     

Impacted Files	Coverage Δ
app/api/custom/group_role_invite.py	70.00% <70.00%> (ø)
app/instance.py	89.42% <100.00%> (+0.10%)	⬆️

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