ci: add build workflow, other GitHub configs, etc.

.github/FUNDING.yml

@@ -0,0 +1 @@
+custom: [ 'https://hysteria.network/docs/donations/' ]

.github/dependabot.yml

@@ -0,0 +1,10 @@
+version: 2
+updates:
+  - package-ecosystem: "gomod"
+    directory: "/"
+    schedule:
+      interval: "daily"
+  - package-ecosystem: "github-actions"
+    directory: "/"
+    schedule:
+      interval: "daily"

.github/workflows/dev-build-hy2.yml

@@ -0,0 +1,40 @@
+name: "Build WIP Hysteria 2"
+
+on:
+  push:
+    branches:
+      - 'wip-hy2'
+
+jobs:
+
+  build:
+    name: Build
+    runs-on: ubuntu-latest
+    env:
+      ACTIONS_ALLOW_UNSECURE_COMMANDS: true
+
+    steps:
+
+      - name: Check out
+        uses: actions/checkout@v3
+
+      - name: Setup Go
+        uses: actions/setup-go@v4
+        with:
+          go-version: '1.20'
+
+      - name: Setup Python # This is for the build script
+        uses: actions/setup-python@v4
+        with:
+          python-version: '3.11'
+
+      - name: Run build script
+        env:
+          HY_APP_PLATFORMS: 'windows/amd64,linux/amd64,linux/arm64,darwin/amd64,darwin/arm64'
+        run: 'python hyperbole.py build -r'
+
+      - name: Archive
+        uses: actions/upload-artifact@v3
+        with:
+          name: hy2-wip-${{ github.sha }}
+          path: build