Make diff-remove-abspath canonifier match on non-whitespace paths only

This avoids swallowing multiple separate paths separated by unrelated
content into one substitution, like here:

orig_p=59856<...>/tcp] -> orig_p=59856/tcp, resp_h=192.150.187.43, resp_p=80/tcp]

testing/scripts/diff-remove-abspath

@@ -9,4 +9,4 @@ else
 fi
 
 $sed 's#/+#/#g' | \
-sed 's#/\([^/]\{1,\}/\)\{1,\}\([^/]\{1,\}\)#<...>/\2#g'
+$sed 's#/([^\t :/]{1,}/){1,}([^\t :/]{1,})#<...>/\2#g'