Migrate from docker to composite run actions

https://docs.github.com/en/actions/creating-actions/creating-a-composite-run-steps-action

It should be able to reuse the go build cache and share the same build
context/environment by using the same default workspace instead of using Docker.

It should resolve an issue such as #21 as well.

action.yml

@@ -35,8 +35,22 @@ inputs:
     description: 'Working directory relative to the root directory.'
     default: '.'
 runs:
-  using: 'docker'
-  image: 'Dockerfile'
+  using: 'composite'
+  steps:
+    - run: $GITHUB_ACTION_PATH/entrypoint.sh
+      shell: bash
+      env:
+        REVIEWDOG_VERSION: v0.10.2
+        GOLANGCI_LINT_VERSION: v1.30.0
+        INPUT_GITHUB_TOKEN: ${{ inputs.github_token }}
+        INPUT_GOLANGCI_LINT_FLAGS: ${{ inputs.golangci_lint_flags }}
+        INPUT_TOOL_NAME: ${{ inputs.tool_name }}
+        INPUT_LEVEL: ${{ inputs.level }}
+        INPUT_REPORTER: ${{ inputs.reporter }}
+        INPUT_FILTER_MODE: ${{ inputs.filter_mode }}
+        INPUT_FAIL_ON_ERROR: ${{ inputs.fail_on_error }}
+        INPUT_REVIEWDOG_FLAGS: ${{ inputs.reviewdog_flags }}
+        INPUT_WORKDIR: ${{ inputs.workdir }}
 branding:
   icon: 'check-circle'
   color: 'blue'

entrypoint.sh

@@ -2,6 +2,17 @@
 
 cd "${GITHUB_WORKSPACE}/${INPUT_WORKDIR}" || exit 1
 
+TEMP_PATH="$(mktemp -d)"
+PATH="${TEMP_PATH}:$PATH"
+
+echo '::group::🐶 Installing reviewdog ... https://github.com/reviewdog/reviewdog'
+curl -sfL https://raw.githubusercontent.com/reviewdog/reviewdog/master/install.sh | sh -s -- -b "${TEMP_PATH}" "${REVIEWDOG_VERSION}" 2>&1
+echo '::endgroup::'
+
+echo '::group::🐶 Installing golangci-lint ... https://github.com/golangci/golangci-lint'
+curl -sfL https://raw.githubusercontent.com/golangci/golangci-lint/master/install.sh | sh -s -- -b "${TEMP_PATH}" "${GOLANGCI_LINT_VERSION}" 2>&1
+echo '::endgroup::'
+
 export REVIEWDOG_GITHUB_API_TOKEN="${INPUT_GITHUB_TOKEN}"
 
 # shellcheck disable=SC2086