patch 9.1.0833: CI: recent ASAN changes do not work for indent tests

Problem:  CI: recent ASAN changes do not work for indent tests
Solution: Move code to runtime/indent/testdir/runtest.vim
          (Aliaksei Budavei)

closes: #15981

Signed-off-by: Aliaksei Budavei <0x000c70@gmail.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>

runtime/indent/testdir/runtest.vim

@@ -14,6 +14,19 @@ set modeline
 set debug=throw
 set nomore
 
+" Remember the directory where we started.
+let indentDir = getcwd()
+cd ../../src/testdir
+
+" Needed for ValgrindOrAsan().
+source shared.vim
+exe 'cd ' .. fnameescape(indentDir)
+
+if ValgrindOrAsan()
+  let g:vim_indent = {"searchpair_timeout": 1024}
+  let g:python_indent = {"searchpair_timeout": 1024}
+endif
+
 au! SwapExists * call HandleSwapExists()
 func HandleSwapExists()
   " Ignore finding a swap file for the test input and output, the user might be