Escape special characters in ref name for update ref

[shravan1k]

Closes #2453

Most of the functions that deal with refs make sure to escape the special characters within the ref's name. The UpdateRef function doesn't seem to call the function that does this substitution of special characters with their encodings. This PR solves this problem and should now successfully patch remote refs if the GetRef function says the corresponding ref exists.

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[codecov]

Codecov Report

Merging #2454 (185b4c5) into master (52cc49e) will not change coverage.
The diff coverage is 100.00%.

@@           Coverage Diff           @@
##           master    #2454   +/-   ##
=======================================
  Coverage   98.03%   98.03%           
=======================================
  Files         122      122           
  Lines       10689    10689           
=======================================
  Hits        10479    10479           
  Misses        144      144           
  Partials       66       66           

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

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[gmlewis]

Thank you, @shravan1k !
Please add a unit test that demonstrates this change in functionality.

[gmlewis]

Whups - checked the wrong box.

Thank you, @shravan1k !
Please add a unit test that demonstrates this change in functionality.

[gmlewis]

Beautiful, @shravan1k ! Thank you!
LGTM.

Awaiting second LGTM from any other contributor to this repo before merging.

[marcelosousa]

LGTM 👍

[gmlewis]

Thank you, @marcelosousa !
Merging.