Adds verification key for Wasm module

[asraa]

Signed-off-by: Asra Ali [email protected]

Commit Message: Adds the abiltiy to specify a verification key to check signatures against in the Wasm module before execution. The change depends on proxy-wasm/proxy-wasm-cpp-host#177
Risk Level: Low/Medium, opt in
Testing:
Docs Changes:
API Considerations: I'd like to change the single pubkey to a VerificationOptions protobuf that would translate to the a struct.
About: #17220

[repokitteh-read-only]

CC @envoyproxy/api-shepherds: Your approval is needed for changes made to api/envoy/.
envoyproxy/api-shepherds assignee is @mattklein123
CC @envoyproxy/api-watchers: FYI only for changes made to api/envoy/.
CC @envoyproxy/dependency-shepherds: Your approval is needed for changes made to (bazel/.*repos.*\.bzl)|(bazel/dependency_imports\.bzl)|(api/bazel/.*\.bzl)|(.*/requirements\.txt)|(.*\.patch).

🐱

Caused by: #17221 was opened by asraa.

see: more, trace.

[github-actions]

This pull request has been automatically marked as stale because it has not had activity in the last 30 days. It will be closed in 7 days if no further activity occurs. Please feel free to give a status update now, ping for review, or re-open when it's ready. Thank you for your contributions!

[github-actions]

This pull request has been automatically closed because it has not had activity in the last 37 days. Please feel free to give a status update now, ping for review, or re-open when it's ready. Thank you for your contributions!