[BUG] mal-formatted markdownfiles : proto-docs tables

[JSHan94]

Describe the bug

Some proto-docs tables look broken as a following figure.

To Reproduce

This is related with a protoc-gen-doc plugin. You can see an issue in here. It said multi-line comments for RPC did not work correctly.

This kind of comments will result in mal-formatted tables.

Suggested Solution

1. One-line comments

• Easy way to solve this problem right now

2. Wait protoc-gen-doc updates

• This PR will fix the problem