Re-enable Miri leak checking in CI.

Author: zachs18

src/bootstrap/mk/Makefile.in

@@ -58,9 +58,8 @@ check-aux:
 		library/core \
 		library/alloc \
 		--no-doc
-	# Some doctests have intentional memory leaks.
 	# Some use file system operations to demonstrate dealing with `Result`.
-	$(Q)MIRIFLAGS="-Zmiri-ignore-leaks -Zmiri-disable-isolation" \
+	$(Q)MIRIFLAGS="-Zmiri-disable-isolation" \
 		$(BOOTSTRAP) miri --stage 2 \
 		library/core \
 		library/alloc \
@@ -70,7 +69,7 @@ check-aux:
 		$(BOOTSTRAP) miri --stage 2 library/std \
 		--no-doc -- \
 		--skip fs:: --skip net:: --skip process:: --skip sys::pal::
-	$(Q)MIRIFLAGS="-Zmiri-ignore-leaks -Zmiri-disable-isolation" \
+	$(Q)MIRIFLAGS="-Zmiri-disable-isolation" \
 		$(BOOTSTRAP) miri --stage 2 library/std \
 		--doc -- \
 		--skip fs:: --skip net:: --skip process:: --skip sys::pal::