Auto merge of #59684 - Centril:rollup-n7pnare, r=Centril

Rollup of 6 pull requests

Successful merges:

 - #59316 (Internal lints take 2)
 - #59663 (Be more direct about borrow contract)
 - #59664 (Updated the documentation of spin_loop and spin_loop_hint)
 - #59666 (Updated the environment description in rustc.)
 - #59669 (Reduce repetition in librustc(_lint) wrt. impl LintPass by using macros)
 - #59677 (rustfix coverage: Skip UI tests with non-json error-format)

Failed merges:

r? @ghost

src/bootstrap/bin/rustc.rs

@@ -316,6 +316,11 @@ fn main() {
         }
     }
 
+    // This is required for internal lints.
+    if stage != "0" {
+        cmd.arg("-Zunstable-options");
+    }
+
     // Force all crates compiled by this compiler to (a) be unstable and (b)
     // allow the `rustc_private` feature to link to other unstable crates
     // also in the sysroot. We also do this for host crates, since those