git: Refactor GitExtractionUnit::updateOrigin to use strings
git: Refactor GitExtractionUnit::updateOrigin to use strings

Simply refactor to use strings in place of char arrays on the heap.

Change-Id: I76e4c3ae4311ceffa3ddba12583a62920bbfe89e
Reviewed-by: Scott Parlane <85029adc3fa41ef14594a57826619713bfe95f25@alliedtelesis.co.nz>
Reviewed-by: Ridge Kennedy <c60c433c4c1ae237d133641099200771ff6f6f30@alliedtelesis.co.nz>
Signed-off-by: Matt Bennett <e3d8681cec70d3da741935b3385821001b249adc@alliedtelesis.co.nz>

alliedtelesis/buildsyspp,ATL-NZ/buildsyspp