Fix since+page pagination bug

[gmlewis]

Fixes: #2112.

[codecov]

Codecov Report

Merging #2218 (8c01a01) into master (b8b15df) will not change coverage.
The diff coverage is 100.00%.

@@           Coverage Diff           @@
##           master    #2218   +/-   ##
=======================================
  Coverage   97.81%   97.81%           
=======================================
  Files         112      112           
  Lines       10117    10117           
=======================================
  Hits         9896     9896           
  Misses        154      154           
  Partials       67       67           

Impacted Files	Coverage Δ
github/github.go	97.62% <100.00%> (ø)

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[gmlewis]

@lonre - Could you please review this PR and approve if you agree with the fix?

[lonre]

@gmlewis Thanks for your help.

I agree with the fix.

[gmlewis]

Thank you, @lonre !
Merging.