fix missing prettier file (#20001)

Summary:
fix missing prettier file
pass all current ci.
facebook/react-native#19987
 [GENERAL] [INTERNAL] [TOOL] - fix missing prettier file.
Closes facebook/react-native#20001

Differential Revision: D8714374

Pulled By: hramos

fbshipit-source-id: acdcb5d84c56d26c55f6262a0a98aefe786de8cb

runAndroid/runAndroid.js

@@ -354,9 +354,7 @@ function startServerInNewWindow(port) {
   const scriptFile = isWindows
     ? 'launchPackager.bat'
     : 'launchPackager.command';
-  const packagerEnvFilename = isWindows
-    ? '.packager.bat'
-    : '.packager.env';
+  const packagerEnvFilename = isWindows ? '.packager.bat' : '.packager.env';
   const portExportContent = isWindows
     ? `set RCT_METRO_PORT=${port}`
     : `export RCT_METRO_PORT=${port}`;
@@ -373,11 +371,14 @@ function startServerInNewWindow(port) {
     '..',
     '..',
     'scripts',
-    packagerEnvFilename
+    packagerEnvFilename,
   );
-  
+
   // ensure we overwrite file by passing the 'w' flag
-  fs.writeFileSync(packagerEnvFile, portExportContent, {encoding: 'utf8', flag: 'w'});
+  fs.writeFileSync(packagerEnvFile, portExportContent, {
+    encoding: 'utf8',
+    flag: 'w',
+  });
 
   if (process.platform === 'darwin') {
     if (terminal) {