Use new plugin key (flutter#7610)

The new plugin key has been uploaded internally; hopefully this fixes
the dev build, but I think I will have to merge this to master to test
it out.

Author: helin24

kokoro/macos_external/release.cfg

@@ -12,7 +12,7 @@ before_action {
   fetch_keystore {
     keystore_resource {
       keystore_config_id: 74840
-      keyname: "flutter-intellij-plugin-auth-token"
+      keyname: "jetbrains-plugin-upload-auth-token"
     }
     keystore_resource {
       keystore_config_id: 74840

tool/kokoro/setup.sh

@@ -27,7 +27,7 @@ setup() {
 
   export FLUTTER_SDK=`pwd`/../flutter
   export FLUTTER_KEYSTORE_ID=74840
-  export FLUTTER_KEYSTORE_NAME=flutter-intellij-plugin-auth-token
+  export FLUTTER_KEYSTORE_NAME=jetbrains-plugin-upload-auth-token
   export FLUTTER_KEYSTORE_JXBROWSER_KEY_NAME=flutter-intellij-plugin-jxbrowser-license-key
   export NO_FS_ROOTS_ACCESS_CHECK=true
 

tool/kokoro/test.bat

@@ -27,7 +27,7 @@ set PATH=%PATH%;%~dp0..\..\..ant\apache-ant-1.10.7\bin
 rem ant -version
 
 set FLUTTER_KEYSTORE_ID=74840
-set FLUTTER_KEYSTORE_NAME=flutter-intellij-plugin-auth-token
+set FLUTTER_KEYSTORE_NAME=jetbrains-plugin-upload-auth-token
 
 cd tool\plugin
 rem dir /s/o ..\..\..