Add TextMatch custom header to other search type custom headers

[DarkMatterV]

Fix TextMatch Option doesn't work when search type is commits topics repositories or issues (#2385)

Fixes: #2385.

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[codecov]

Codecov Report

Merging #2388 (398d048) into master (697804f) will increase coverage by 0.00%.
The diff coverage is 100.00%.

@@ Coverage Diff @@## master #2388 +/- ##
=======================================
Coverage 98.06% 98.06% =======================================
Files 119 119 Lines 10545 10548 +3 =======================================
+ Hits 10341 10344 +3 
Misses 140 140 Partials 64 64 

Impacted Files	Coverage Δ
github/search.go	93.61% <100.00%> (+0.13%)	⬆️
github/repos.go	98.66% <0.00%> (+<0.01%)	⬆️

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[gmlewis]

Thank you, @DarkMatterV !
Please make sure to run the modified files through gofmt.
See CONTRIBUTING.md for more details.

[gmlewis]

Thank you, @DarkMatterV !
LGTM.

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

[raynigon]

LGTM

[gmlewis]

Thank you, @raynigon !
Merging.