generate docs for proto

[tejal29]

Relates to #3023

Description

Generates API docs for skaffold Trigger, Control and Event API from skaffold.proto using
https://github.com/pseudomuto/protoc-gen-doc/tree/f2fcd98d4c7d0203f2eb091c3a3cb4f16ba233a7#invoking-the-plugin

User facing changes
yes

Before
no reference generated for all skaffold protos.

After
Please see http://35.236.87.39:1313/docs/references/api/

Note: This page is not discoverable to user and not linked anywhere.
The reason,

• this is POC for how the generated API docs look
• most of the fields in the proto are missing description and we shd add those before linking it in skaffold.dev/references

Next PRs.
n/a

Submitter Checklist

These are the criteria that every PR should meet, please check them off as you
review them:

• Includes unit tests
• Mentions any output changes.
• Adds documentation as needed: user docs, YAML reference, CLI reference.
• Adds integration tests if needed.

See the contribution guide for more details.

Reviewer Notes

• The code flow looks good.
• Unit test added.
• User facing changes look good.

Release Notes

[tejal29]

This file is generated by https://github.com/pseudomuto/protoc-gen-doc/tree/f2fcd98d4c7d0203f2eb091c3a3cb4f16ba233a7#invoking-the-plugin
Please see ./hack/proto/Dockerfile for details.

[container-tools-bot]

Please visit http://35.236.87.39:1313 to view changes to the docs.

[codecov]

Codecov Report

Merging #3067 into master will not change coverage.
The diff coverage is n/a.

[balopat]

Looks great!
We should add the link to the front matter as well on http://35.236.87.39:1313/docs/references/, also we should make sure it shows up in the menu:

[tejal29]

Looks great!
We should add the link to the front matter as well on http://35.236.87.39:1313/docs/references/, also we should make sure it shows up in the menu:

I listed the reason, why this is not discoverable in the description here
#3067 (comment)

The reason,

this is POC for how the generated API docs look
most of the fields in the proto are missing description and we shd add those before linking it in skaffold.dev/references

Do you still think its ok to show ?

[balopat]

Fair enough, let's not link it in just yet, let's iterate on it a bit more