Adds uptime tracking for healthcheck

[ZRexshima]

Description of your PR

Adds uptime tracking for the bot

Describe your changes

Added

• Uses datetime to capture start time of bot process.
• Added method for calculating running time of bot (timedelta)
• Added output formatter method for embed

Fixed

Changed

• Changes hc_embed function to add boot time to parameters and
• Changes bot's main.py to capture boot time.

Removed

• N/A

Issue link

Closes #160

Checklist

• Does an issue of this PR exist and have you linked it?
• Have your ran pre-commit over your PR?
• Was this PR branched off from master?
• Is this PR merging to master?