Bug #12360195 MTR DOES NOT IGNORE TABS IN EXPERIMENTAL FILE

Instead of just filtering space, filter white space (\s)
I left the default.experimental file as is, with tabs.

mysql-test/mysql-test-run.pl

@@ -1123,7 +1123,7 @@ sub command_line_setup {
 	chomp;
 	# remove comments (# foo) at the beginning of the line, or after a 
 	# blank at the end of the line
-	s/( +|^)#.*$//;
+	s/(\s+|^)#.*$//;
 	# If @ platform specifier given, use this entry only if it contains
 	# @<platform> or @!<xxx> where xxx != platform
 	if (/\@.*/)
@@ -1134,8 +1134,8 @@ sub command_line_setup {
 	  s/\@.*$//;
 	}
 	# remove whitespace
-	s/^ +//;              
-	s/ +$//;
+	s/^\s+//;
+	s/\s+$//;
 	# if nothing left, don't need to remember this line
 	if ( $_ eq "" ) {
 	  next;