[clang-tools-extra] [clang-tidy] Run analysis even with no checks (as long as `--allow-no-checks` is passed) (PR #194006)

[Victor Chernyakin via cfe-commits]

================
@@ -1,3 +1,3 @@
-// RUN: clang-tidy -checks=-*,google-explicit-constructor %s 2>&1 | FileCheck %s
+// RUN: clang-tidy -checks=-*,google-explicit-constructor %s -- 2>&1 | FileCheck %s
----------------
localspook wrote:

I added all these `--` to work around #182526. Without it, the tests fail with
```
error: PCH file '[...]/cmake_pch.hxx.pch' uses an older format that is no longer supported
```
 I don't like that we're adding so many workarounds for that problem, we should come up with a proper fix, I just don't know what that would be right now.

https://github.com/llvm/llvm-project/pull/194006