Remove CI caching

Github actions is terrible.

Author: nhooyr

.github/workflows/ci.yml

@@ -6,12 +6,6 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v1
-      - uses: actions/cache@v1
-        with:
-          path: ~/go/pkg/mod
-          key: ${{ runner.os }}-go-${{ hashFiles('**/go.sum') }}
-          restore-keys: |
-            ${{ runner.os }}-go-
       - name: make fmt
         uses: ./ci/image
         with:
@@ -21,12 +15,6 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v1
-      - uses: actions/cache@v1
-        with:
-          path: ~/go/pkg/mod
-          key: ${{ runner.os }}-go-${{ hashFiles('**/go.sum') }}
-          restore-keys: |
-            ${{ runner.os }}-go-
       - name: make lint
         uses: ./ci/image
         with:
@@ -36,12 +24,6 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v1
-      - uses: actions/cache@v1
-        with:
-          path: ~/go/pkg/mod
-          key: ${{ runner.os }}-go-${{ hashFiles('**/go.sum') }}
-          restore-keys: |
-            ${{ runner.os }}-go-
       - name: make test
         uses: ./ci/image
         with: