Add documentation for executor secret

Dockerfile

@@ -141,6 +141,7 @@ ENV _APP_SERVER=swoole \
     _APP_FUNCTIONS_CPUS=1 \
     _APP_FUNCTIONS_MEMORY=128 \
     _APP_FUNCTIONS_MEMORY_SWAP=128 \
+    _APP_EXECUTOR_SECRET=a-random-secret \
     _APP_SETUP=self-hosted \
     _APP_VERSION=$VERSION \
     _APP_USAGE_STATS=enabled \

app/config/variables.php

@@ -453,6 +453,15 @@ return [
                 'question' => '',
                 'filter' => ''
             ],
+            [
+                'name' => '_APP_EXECUTOR_SECRET',
+                'description' => 'The secret key used by appwrite to communicate with the function executor. Make sure to change this!',
+                'introduction' => '0.11.0',
+                'default' => 'your-secret-key',
+                'required' => false,
+                'question' => '',
+                'filter' => ''
+            ],
             [
                 'name' => '_APP_FUNCTIONS_ENVS',
                 'description' => 'Deprectated with 0.8.0, use \'_APP_FUNCTIONS_RUNTIMES\' instead!',

app/views/install/compose.phtml

@@ -105,6 +105,7 @@ services:
       - _APP_FUNCTIONS_CPUS
       - _APP_FUNCTIONS_MEMORY
       - _APP_FUNCTIONS_MEMORY_SWAP
+      - _APP_EXECUTOR_SECRET
       - _APP_FUNCTIONS_RUNTIMES
 
   appwrite-realtime:
@@ -311,6 +312,7 @@ services:
       - _APP_FUNCTIONS_CPUS
       - _APP_FUNCTIONS_MEMORY
       - _APP_FUNCTIONS_MEMORY_SWAP
+      - _APP_EXECUTOR_SECRET
       - _APP_FUNCTIONS_RUNTIMES
       - _APP_USAGE_STATS