[GH-195] Send notification to channel when issue gets reopened

[maruTA-bis5]

Summary

Send notification to channel when the issue gets reopened.

Ticket Link

Fixes #195

[mattermod]

Hello @maruTA-bis5,

Thanks for your pull request! A Core Committer will review your pull request soon. For code contributions, you can learn more about the review process here.

[codecov]

Codecov Report

Merging #267 (5d507c8) into master (5f463d2) will increase coverage by 0.06%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##           master     #267      +/-   ##
==========================================
+ Coverage   39.38%   39.45%   +0.06%     
==========================================
  Files          16       16              
  Lines        1795     1797       +2     
==========================================
+ Hits          707      709       +2     
  Misses       1011     1011              
  Partials       77       77              

Impacted Files	Coverage Δ
server/webhook/issue.go	83.11% <100.00%> (+0.45%)	⬆️

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[iomodo]

Looks good @maruTA-bis5 !

[mattermod]

This PR has been automatically labelled "stale" because it hasn't had recent activity.
A core team member will check in on the status of the PR to help with questions.
Thank you for your contribution!

/cc @jasonblais @jfrerich @emilyacook

[emilyacook]

Thanks for participating in Hacktoberfest! You can claim your sticker set here: https://get.printfection.com/hacktober21/4144583267 @maruTA-bis5

[dipak-demansol]

@hanzei LGTM but after a call with dylan i will add a Final Review.

[dipak-demansol]

LGTM For The New & Old Issue when It Reopen then i'm Getting The Notification.