Upgrade to Node 14 for Actions (#2928)

Summary:
I believe that matches what we have internally. This has been causing some upgrades to fail.

Pull Request resolved: https://github.com/facebook/flipper/pull/2928

Reviewed By: aigoncharov

Differential Revision: D31324394

Pulled By: passy

fbshipit-source-id: eec38dcc6322e3e8957bbc20bf74d343855be8c0

.github/workflows/react-native-example.yml

@@ -10,7 +10,7 @@ jobs:
     - uses: actions/checkout@v2
     - uses: actions/setup-node@v2.1.5
       with:
-        node-version: 12.x
+        node-version: 14.x
     - uses: maxim-lobanov/setup-cocoapods@v1
       with:
         # Path to Podfile.lock file to determine Cocoapods version
@@ -37,7 +37,7 @@ jobs:
     - uses: actions/checkout@v2
     - uses: actions/setup-node@v2.1.5
       with:
-        node-version: 12.x
+        node-version: 14.x
     - name: set up JDK 1.8
       uses: actions/setup-java@v1
       with: