Upgrade to Node.js 14 (#15822)

* set engines.node to >=12

* set engines.node to >=12

* Update node-versions.md

* update Node.js version in Actions workflows

* Update .node-version

* Update references to Node.js version from 12 to 14

* Update Dockerfile to use Node.js 14

* set engines.node to safe "12 - 14" range

.github/workflows/sync-algolia-search-indices.yml

@@ -15,7 +15,7 @@ jobs:
       uses: actions/checkout@v2
     - uses: actions/setup-node@v1
       with:
-        node-version: "12.x"
+        node-version: 14.x
     - name: cache node modules
       uses: actions/cache@v1
       with:

.github/workflows/test-translations.yml

@@ -19,7 +19,7 @@ jobs:
       - name: Setup node
         uses: actions/setup-node@v1
         with:
-          node-version: 12.x
+          node-version: 14.x
 
       - name: Get npm cache directory
         id: npm-cache
@@ -57,7 +57,7 @@ jobs:
       - name: Setup node
         uses: actions/setup-node@v1
         with:
-          node-version: 12.x
+          node-version: 14.x
 
       - name: Get npm cache directory
         id: npm-cache

.github/workflows/test-windows.yml

@@ -20,7 +20,7 @@ jobs:
       - name: Setup node
         uses: actions/setup-node@v1
         with:
-          node-version: 12.x
+          node-version: 14.x
 
       - name: Get npm cache directory
         id: npm-cache
@@ -58,7 +58,7 @@ jobs:
       - name: Setup node
         uses: actions/setup-node@v1
         with:
-          node-version: 12.x
+          node-version: 14.x
 
       - name: Get npm cache directory
         id: npm-cache

.github/workflows/test.yml

@@ -23,7 +23,7 @@ jobs:
       - name: Setup node
         uses: actions/setup-node@v1
         with:
-          node-version: 12.x
+          node-version: 14.x
 
       - name: Get npm cache directory
         id: npm-cache
@@ -60,7 +60,7 @@ jobs:
       - name: Setup node
         uses: actions/setup-node@v1
         with:
-          node-version: 12.x
+          node-version: 14.x
 
       - name: Get npm cache directory
         id: npm-cache