Add Settings window to Agent UI

Agent systray UI has been extended with
a setting window that allows configuring 
management URL, admin URL and 
supports pre-shared key.
While for the Netbird managed version 
the Settings are not necessary, it helps
to properly configure the self-hosted version.

.github/workflows/golang-test-linux.yml

@@ -25,7 +25,7 @@ jobs:
         uses: actions/checkout@v2
 
       - name: Install dependencies
-        run: sudo apt update && sudo apt install -y -q libgtk-3-dev libappindicator3-dev libayatana-appindicator3-dev
+        run: sudo apt update && sudo apt install -y -q libgtk-3-dev libappindicator3-dev libayatana-appindicator3-dev libgl1-mesa-dev xorg-dev
 
       - name: Install modules
         run: go mod tidy

.github/workflows/golangci-lint.yml

@@ -8,9 +8,10 @@ jobs:
       - uses: actions/checkout@v2
 
       - name: Install dependencies
-        run: sudo apt update && sudo apt install -y -q libgtk-3-dev libappindicator3-dev libayatana-appindicator3-dev
-
+        run: sudo apt update && sudo apt install -y -q libgtk-3-dev libappindicator3-dev libayatana-appindicator3-dev libgl1-mesa-dev xorg-dev
       - name: golangci-lint
         uses: golangci/golangci-lint-action@v2
+        with:
+          args: --timeout=6m