Improve default metrics collected by SolrShardReporter

SolrShardReporter's default metric filters have two problems:

• "Tlog.*" should be "TLOG.*" (a bug)
• "UPDATE
  ./update/.*requests" should be "UPDATE
  ./update.*requests"  (notice removal of one '/')

Today, the first was fixed and tagged to the issue that incorrectly made this change – SOLR-12690.  What remains is the other.

CC ab