typescript: Stop running yarn install concurrently

Since `yarn install` doesn't support running concurrently lets call
`synchronized` to avoid that.

Author: jnatten

.gitignore

@@ -10,3 +10,4 @@ metals.sbt
 
 /typescript/**/node_modules
 /typescript/**/build
+/typescript/.yarn_installed

project/OpenApiTypescriptPlugin.scala

@@ -64,7 +64,9 @@ object OpenApiTypescriptPlugin extends AutoPlugin {
   }
 
   def generateOpenapiTypescriptFile(appName: String): Unit = {
-    runCommand("yarn --cwd typescript/types-backend/ install")
+    synchronized {
+      runCommand("yarn --cwd typescript/types-backend/ install")
+    }
     runCommand(s"yarn --cwd typescript/types-backend/ generate-typescript $appName")
   }