Fix Sentry source maps (#20616)

Sentry source maps were broken a few weeks back, and then fixed in the
PR #20122. The fix was to add a leading slash to our file paths in the
source maps.

This fix was accidentally undone recently in #19552, which is an
otherwise unrelated change. I suspect this was committed accidentally
due to local testing of #20122 around the same time.

This PR restores the file path change made in #20122

development/sentry-upload-artifacts.sh

@@ -31,7 +31,7 @@ function upload_sourcemaps {
   local release="${1}"; shift
   local dist_directory="${1}"; shift
 
-  sentry-cli releases files "${release}" upload-sourcemaps "${dist_directory}"/chrome/*.js "${dist_directory}"/sourcemaps/ --rewrite --url-prefix 'metamask'
+  sentry-cli releases files "${release}" upload-sourcemaps "${dist_directory}"/chrome/*.js "${dist_directory}"/sourcemaps/ --rewrite --url-prefix '/metamask'
 }
 
 function main {