Add deployment permissions configuration for prerelease builds

Squashed commit of the following:

commit 30c0349
Author: scripthunter7 <d.tota@adguard.com>
Date:   Fri Nov 28 18:24:50 2025 +0100

    Add deployment permissions configuration for prerelease builds

Author: totadavid95

bamboo-specs/permissions-prerelease.yaml

@@ -0,0 +1,22 @@
+---
+version: 2
+deployment:
+  name: VSCode Adblock Syntax - Deploy Prerelease
+deployment-permissions:
+  - groups:
+      - extensions-developers
+    permissions:
+      - view
+environment-permissions:
+  - marketplace.visualstudio.com:
+      - groups:
+          - extensions-developers
+        permissions:
+          - view
+          - deploy
+  - open-vsx.org:
+      - groups:
+          - extensions-developers
+        permissions:
+          - view
+          - deploy