[lit testing] Fix xfail-cl.py test worker count

This would fail in test environments with < 3 hardware threads.

Differential Revision: https://reviews.llvm.org/D99858

Author: luismarques

llvm/utils/lit/tests/xfail-cl.py

@@ -3,7 +3,7 @@
 # RUN: %{lit} --xfail 'false.txt;false2.txt' %{inputs}/xfail-cl | FileCheck --check-prefix=CHECK-FILTER %s
 # RUN: env LIT_XFAIL='false.txt;false2.txt' %{lit} %{inputs}/xfail-cl | FileCheck --check-prefix=CHECK-FILTER %s
 # END.
-# CHECK-FILTER: Testing: 3 tests, 3 workers
+# CHECK-FILTER: Testing: 3 tests, {{[1-3]}} workers
 # CHECK-FILTER-DAG: XFAIL: top-level-suite :: false.txt
 # CHECK-FILTER-DAG: XFAIL: top-level-suite :: false2.txt
 # CHECK-FILTER-DAG: PASS: top-level-suite :: true.txt