patch 8.2.3469: some files with json syntax are not recognized

Problem:    Some files with json syntax are not recognized.
Solution:   Add a few file patterns. (Emiliano Ruiz Carletti, closes #8947)

runtime/filetype.vim

@@ -876,6 +876,9 @@ au BufNewFile,BufRead *.json-patch			setf json
 " Jupyter Notebook is also json
 au BufNewFile,BufRead *.ipynb				setf json
 
+" Other files that look like json
+au BufNewFile,BufRead .babelrc,.eslintrc,.prettierrc,.firebaserc  setf json
+
 " JSONC
 au BufNewFile,BufRead *.jsonc			setf jsonc
 

src/testdir/test_filetype.vim

@@ -259,7 +259,7 @@ let s:filename_checks = {
     \ 'jgraph': ['file.jgr'],
     \ 'jovial': ['file.jov', 'file.j73', 'file.jovial'],
     \ 'jproperties': ['file.properties', 'file.properties_xx', 'file.properties_xx_xx', 'some.properties_xx_xx_file'],
-    \ 'json': ['file.json', 'file.jsonp', 'file.json-patch', 'file.webmanifest', 'Pipfile.lock', 'file.ipynb'],
+    \ 'json': ['file.json', 'file.jsonp', 'file.json-patch', 'file.webmanifest', 'Pipfile.lock', 'file.ipynb', '.babelrc', '.eslintrc', '.prettierrc', '.firebaserc'],
     \ 'jsonc': ['file.jsonc'],
     \ 'jsp': ['file.jsp'],
     \ 'julia': ['file.jl'],

src/version.c

@@ -757,6 +757,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    3469,
 /**/
     3468,
 /**/