Merge pull request #18205 from edx/thallada/sfe-modal-improvements

Upgrade SFE, unscrollable body when modal is open.

package.json

@@ -5,7 +5,7 @@
     "@edx/cookie-policy-banner": "1.1.8",
     "@edx/edx-bootstrap": "0.4.3",
     "@edx/paragon": "2.6.4",
-    "@edx/studio-frontend": "1.9.9",
+    "@edx/studio-frontend": "1.9.12",
     "babel-core": "6.26.0",
     "babel-loader": "6.4.1",
     "babel-plugin-transform-class-properties": "6.24.1",