[llvm] [LIT] Print discovered tests and percentages (PR #66057)

[Thomas Preud'homme via llvm-commits]

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@@ -335,10 +336,11 @@ def print_group(tests, code, shown_codes):
     sys.stdout.write("\n")
 
 
-def print_summary(tests_by_code, quiet, elapsed):
+def print_summary(total_tests, tests_by_code, quiet, elapsed):
     if not quiet:
         print("\nTesting Time: %.2fs" % elapsed)
 
+    print("\nTotal Discovered Tests: %s" % (total_tests))
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RoboTux wrote:

```suggestion
    print(f"\nTotal Discovered Tests: {total_tests}")
```

https://github.com/llvm/llvm-project/pull/66057