revert(3p/git): Revert merge of git upstream at v2.26.2

This causes cgit to serve error pages, which is undesirable.

This reverts commit 5229c9b232, reversing
changes made to f2b211131f.

third_party/git/url.c

@@ -5,7 +5,7 @@ int is_urlschemechar(int first_flag, int ch)
 {
 	/*
 	 * The set of valid URL schemes, as per STD66 (RFC3986) is
-	 * '[A-Za-z][A-Za-z0-9+.-]*'. But use slightly looser check
+	 * '[A-Za-z][A-Za-z0-9+.-]*'. But use sightly looser check
 	 * of '[A-Za-z0-9][A-Za-z0-9+.-]*' because earlier version
 	 * of check used '[A-Za-z0-9]+' so not to break any remote
 	 * helpers.
@@ -86,12 +86,6 @@ char *url_decode_mem(const char *url, int len)
 	return url_decode_internal(&url, len, NULL, &out, 0);
 }
 
-char *url_percent_decode(const char *encoded)
-{
-	struct strbuf out = STRBUF_INIT;
-	return url_decode_internal(&encoded, strlen(encoded), NULL, &out, 0);
-}
-
 char *url_decode_parameter_name(const char **query)
 {
 	struct strbuf out = STRBUF_INIT;