Update Repository to include WatchersCount

[KarolGrzesiak]

Resolves #2181

[codecov]

Codecov Report

Merging #2182 into master will decrease coverage by 0.85%.
The diff coverage is 35.71%.

@@            Coverage Diff             @@
##           master    #2182      +/-   ##
==========================================
- Coverage   65.88%   65.02%   -0.86%     
==========================================
  Files         546      547       +1     
  Lines       14293    14280      -13     
  Branches      838      835       -3     
==========================================
- Hits         9417     9286     -131     
- Misses       4718     4720       +2     
- Partials      158      274     +116     

Impacted Files	Coverage Δ
Octokit/Models/Request/NewProjectCard.cs	27.27% <0.00%> (ø)
Octokit/Models/Response/Repository.cs	5.68% <0.00%> (-0.14%)	⬇️
Octokit/Models/Response/CheckRunRequestedAction.cs	42.85% <42.85%> (ø)
Octokit/Clients/ChecksClient.cs	100.00% <100.00%> (ø)
.../Response/ActivityPayloads/CheckRunEventPayload.cs	100.00% <100.00%> (ø)
Octokit/Helpers/AuthorizationExtensions.cs	82.35% <0.00%> (-17.65%)	⬇️
Octokit/Clients/MigrationsClient.cs	83.33% <0.00%> (-16.67%)	⬇️
Octokit/Clients/StatisticsClient.cs	86.20% <0.00%> (-13.80%)	⬇️
Octokit/Clients/GitHubAppInstallationsClient.cs	50.00% <0.00%> (-12.50%)	⬇️
Octokit/Clients/RepositoryInvitationsClient.cs	67.85% <0.00%> (-10.72%)	⬇️
... and 34 more

[shiftkey]

@KarolGrzesiak thanks for opening this up!

Can we mark SubscribersCount as obsolete while we're making this change?

        [Obsolete("Update your code to use WatchersCount as this field will stop containing data in the future")]
        public int SubscribersCount { get; protected set; }

[shiftkey]

I've tidied this up so we can get it out in an update. Thanks for getting it started @KarolGrzesiak!

[shiftkey]

release_notes: Add WatchersCount to Repository response model