Basic golang CI setup (#360)

* bskyweb: Makefile and dev env

This matches the setup for local dev testing in atproto and indigo
repos.

* gitignore: don't ignore self and .github/

* CI: golang build+test and lint actions

* bskyweb: better use of godotenv

A recent change from indigo.

* prettier: ignore top-level app.json

* CI: bump from golang 1.19 to 1.20

* bskyweb: update to golang 1.20

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

@@ -0,0 +1,43 @@
+name: golang
+
+on:
+  pull_request:
+  push:
+    branches:
+      - main
+
+concurrency:
+  group: '${{ github.workflow }}-${{ github.head_ref || github.ref }}'
+  cancel-in-progress: true
+
+jobs:
+  build-and-test:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Git Checkout
+        uses: actions/checkout@v3
+      - name: Set up Go tooling
+        uses: actions/setup-go@v3
+        with:
+          go-version: 1.20
+      - name: Dummy JS File
+        run: touch bskyweb/static/js/blah.js
+      - name: Check
+        run: cd bskyweb/ && make check
+      - name: Build (binary)
+        run: cd bskyweb/ && make build
+      - name: Test
+        run: cd bskyweb/ && make test
+  lint:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Git Checkout
+        uses: actions/checkout@v3
+      - name: Set up Go tooling
+        uses: actions/setup-go@v3
+        with:
+          go-version: 1.20
+      - name: Dummy JS File
+        run: touch bskyweb/static/js/blah.js
+      - name: Lint
+        run: cd bskyweb/ &&  make lint