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.