manifest_xml: do not allow / before : in scp-like syntax

Since git doesn't treat these as ssh:// URIs, we shouldn't either.

Bug: https://g-issues.gerritcodereview.com/issues/40010331
Change-Id: I001f49be30395187cac447d09cb5a6c29e95768b
Reviewed-on: https://gerrit-review.googlesource.com/c/git-repo/+/398517
Tested-by: Mike Frysinger <vapier@google.com>
Reviewed-by: Jason Chang <jasonnc@google.com>
Commit-Queue: Mike Frysinger <vapier@google.com>
diff --git a/manifest_xml.py b/manifest_xml.py
index edbebaa..7e533a0 100644
--- a/manifest_xml.py
+++ b/manifest_xml.py
@@ -134,7 +134,7 @@
     parsed_url = urllib.parse.urlparse(url)
 
     # This matches patterns like "git@github.com:foo/bar".
-    scp_like_url_re = r"^[^:]+@[^:]+:[^/]+/"
+    scp_like_url_re = r"^[^/:]+@[^/:]+:[^/]+/"
 
     # If our URL is missing a schema and matches git's
     # SCP-like syntax we should convert it to a proper