Bump intersection-observer from 0.11.0 to 0.12.0 (#15342)

Bumps [intersection-observer](https://github.com/w3c/IntersectionObserver) from 0.11.0 to 0.12.0.
- [Release notes](https://github.com/w3c/IntersectionObserver/releases)
- [Commits](https://github.com/w3c/IntersectionObserver/commits)

Signed-off-by: dependabot[bot] <support@github.com>

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

package.json

@@ -102,7 +102,7 @@
     "http-link-header": "^1.0.3",
     "immutable": "^3.8.2",
     "imports-loader": "^1.2.0",
-    "intersection-observer": "^0.11.0",
+    "intersection-observer": "^0.12.0",
     "intl": "^1.2.5",
     "intl-messageformat": "^2.2.0",
     "intl-relativeformat": "^6.4.3",