Enable sanitizer-leak test case

Author: tmiasko

src/test/run-make-fulldeps/sanitizer-leak/Makefile

@@ -3,8 +3,6 @@
 # needs-sanitizer-support
 # only-linux
 # only-x86_64
-# ignore-test
-# FIXME(#46126) ThinLTO for libstd broke this test
 
 all:
 	$(RUSTC) -C opt-level=1 -g -Z sanitizer=leak -Z print-link-args leak.rs | $(CGREP) librustc_rt.lsan