docs: add security response process

[moolen]

This PR proposes a security incident response process / guideline just to have it in case.

This is taken from the CNC/tag-security Project Resources. Minor adaptations have been made.

[sonarcloud]

Quality Gate passed

Kudos, no new issues were introduced!

0 New issues
0 Security Hotspots
No data about Coverage
No data about Duplication

See analysis details on SonarCloud

[Skarlso]

Suggested change

	Triaging problems allows maintainers to focus resources on the most critically
	impacting problems. Potential security problems should be evaluated against the
	following information:
	Triaging issues allows maintainers to focus resources on the most critically
	impacting problems. Potential security risks should be evaluated against the
	following information:

[Skarlso]

Suggested change

	a helpful tool in evaluating the criticality of reported problems.
	a helpful tool in evaluating the criticality of reported issues.

[Skarlso]

Suggested change

	Respond to the reporter and notify them you have received the problem and have
	begun reviewing it. Remind them of the [embargo policy](https://github.com/cncf/tag-security/blob/231b87f371274b2d68def2c6a35a719210836191/project-resources/templates/embargo-policy.md), and provide them
	information on who to contact/follow-up with if they have questions. Estimate a
	time frame that they can expect to receive an update on the problem. Create a
	calendar reminder to contact them again by that date to provide an update.
	Respond to the reporter and notify them that you have received and begun reviewing the problem. Remind them of the [embargo policy](https://github.com/cncf/tag-security/blob/231b87f371274b2d68def2c6a35a719210836191/project-resources/templates/embargo-policy.md), and provide them
	information on who to contact/follow-up with if they have questions. Estimate when they can expect to receive an update. Create a calendar reminder to contact them again by that date to provide an update.

[Skarlso]

uh I think I messed up the linebreaks a bit here...

[Skarlso]

LGTM, just have a couple of suggestions for removing duplicate words and adding a bit of clarity.

[moolen]

Thanks! I've opened #3056 to get your suggestions in!