[WebAssembly] Remove a temporarily added RUN line

[aheejin]

Summary

This RUN line was added as a temporary measure to undo the damage done
by D79655. Everyone's build system should be fine by now.

[tlively]

Wow, that bug is wild!

clang/test/CodeGenCXX/wasm-eh.cpp

 // REQUIRES: webassembly-registered-target
-// https://reviews.llvm.org/D79655 temporarily added a RUN line that was missing
-// a -o flag and wrote to the source dir. The file it wrote was then interpreted
-// as a test without RUN line, breaking bots. FIXME: Remove this rm line once
-// it's been in the tree long enough to clean up everyone's build dirs.
-// Removing this June 2020 should be fine.
-// RUN: rm -f %S/wasm-eh.ll
 // RUN: %clang_cc1 %s -triple wasm32-unknown-unknown -fms-extensions -fexceptions -fcxx-exceptions -fwasm-exceptions -target-feature +exception-handling -emit-llvm -o - -std=c++11 | FileCheck %s
 // RUN: %clang_cc1 %s -triple wasm64-unknown-unknown -fms-extensions -fexceptions -fcxx-exceptions -fwasm-exceptions -target-feature +exception-handling -emit-llvm -o - -std=c++11 | FileCheck %s
 
 void may_throw();
 void dont_throw() noexcept;
 
 struct Cleanup {
   ~Cleanup() { dont_throw(); }