Disable local fallback by default

We don't want people to get used to this.

PiperOrigin-RevId: 158508816
diff --git a/src/main/java/com/google/devtools/build/lib/remote/RemoteOptions.java b/src/main/java/com/google/devtools/build/lib/remote/RemoteOptions.java
index d779aa7..35dd9f5 100644
--- a/src/main/java/com/google/devtools/build/lib/remote/RemoteOptions.java
+++ b/src/main/java/com/google/devtools/build/lib/remote/RemoteOptions.java
@@ -89,7 +89,7 @@
 
   @Option(
     name = "remote_local_fallback",
-    defaultValue = "true",
+    defaultValue = "false",
     category = "remote",
     help = "Whether to fall back to standalone local execution strategy if remote execution fails."
   )