Bug 1549396 - Disable flaky GC test. r=jandem

Differential Revision: https://phabricator.services.mozilla.com/D30058

--HG--
extra : moz-landing-system : lando

js/src/jit-test/tests/gc/bug-1215678.js

@@ -1,10 +0,0 @@
-// |jit-test| error: ReferenceError
-if (!('oomTest' in this))
-    a;
-
-enableShellAllocationMetadataBuilder()
-oomTest(() => {
-  newGlobal()
-})
-gczeal(9, 1);
-a;

js/src/jsapi-tests/binast/jit-test.ignore

@@ -1211,7 +1211,6 @@ gc/bug-1209001.js
 gc/bug-1215363-1.js
 gc/bug-1215363-2.js
 gc/bug-1215363-3.js
-gc/bug-1215678.js
 gc/bug-1221359.js
 gc/bug-1226896.js
 gc/bug-1234410.js