feat: Enable cloudevent conversion logic (#321)

This commit re-enables the logic to automatically convert between legacy
and cloudevent request payloads to match the configured signature type.
This was reverted in #289. Now that we have a plan for how it will
work, we should re-enable it.

This reverts commit d894b49.

Author: matthewrobertson

.github/workflows/conformance.yml

@@ -32,7 +32,7 @@ jobs:
       run: npm install
 
     - name: Run HTTP conformance tests
-      uses: GoogleCloudPlatform/functions-framework-conformance/action@v0.3.10
+      uses: GoogleCloudPlatform/functions-framework-conformance/action@v1.0.0
       with:
         functionType: 'http'
         useBuildpacks: false
@@ -41,19 +41,19 @@ jobs:
         cmd: "'npm start -- --target=writeHttp --signature-type=http'"
 
     - name: Run event conformance tests
-      uses: GoogleCloudPlatform/functions-framework-conformance/action@v0.3.10
+      uses: GoogleCloudPlatform/functions-framework-conformance/action@v1.0.0
       with:
         functionType: 'legacyevent'
         useBuildpacks: false
-        validateMapping: false
+        validateMapping: true
         workingDirectory: 'test/conformance'
         cmd: "'npm start -- --target=writeLegacyEvent --signature-type=event'"
 
     - name: Run cloudevent conformance tests
-      uses: GoogleCloudPlatform/functions-framework-conformance/action@v0.3.10
+      uses: GoogleCloudPlatform/functions-framework-conformance/action@v1.0.0
       with:
         functionType: 'cloudevent'
         useBuildpacks: false
-        validateMapping: false
+        validateMapping: true
         workingDirectory: 'test/conformance'
         cmd: "'npm start -- --target=writeCloudEvent --signature-type=cloudevent'"