Add Github Actions

[ericnakagawa]

• Add a Github action that verifies YAML front matter, new proposals that do not pass should not be allowable to merge.

• Additionally, add @bowd 's CGP viewer tool to ensure body of markdown matches what is provided in corresponding folder.

### Tasks
- [x] Add a Github action that verifies YAML front matter, new proposals that do not pass should not be allowable to merge.
- [ ] Add @bowd 's CGP viewer tool to ensure body of markdown matches what is provided in corresponding folder.

[0xzoz]

Task one was addressed in #414

[ericnakagawa]

Checking with @bowd if he can add an additional CI check to /governance to check payload matches.

[work-0xj4an]

@ericnakagawa anynnews about @bowd "add an additional CI check to /governance to check payload matches"