escape filename when assemble URL (#22850)
Fixes: #22843
### Cause:
affdd40296/services/repository/files/content.go (L161)
Previously, we did not escape the **"%"** that might be in "treePath"
when call "url.parse()".
This function will check whether "%" is the beginning of an escape
character. Obviously, the "%" in the example (hello%mother.txt) is not
that. So, the function will return a error.
### Solution:
We can escape "treePath" by call "url.PathEscape()" function firstly.
### Screenshot:
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Signed-off-by: Andrew Thornton <art27@cantab.net>
Co-authored-by: Andrew Thornton <art27@cantab.net>
51ab495198
