chore: make RELEASE.md more clear

[weiseng18]

Problem

Improve clarity in RELEASE.md to reduce mental load

Solution

• Added what a release PR should look like
• Added what a bump PR should look like

Checklist

• If the branch was not created off latest develop, merge locally
• Using latest develop and master, do git diff --stat master while in develop branch. Ensure that the diff is not too large

Notes

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