new(rules): add modification to authorized keys rule

[loresuso]

What type of PR is this?

Uncomment one (or more) /kind <> lines:

/kind feature

/kind bug

/kind cleanup

/kind design

/kind documentation

/kind failing-test

Any specific area of the project related to this PR?

Uncomment one (or more) /area <> lines:

/area rules

/area registry

/area build

/area documentation

Proposed rule maturity level

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/area maturity-stable

/area maturity-incubating

/area maturity-sandbox

/area maturity-deprecated

What this PR does / why we need it: Adding ssh keys to authorized_keys file is a common persistence/escalation technique, as reported here. Read rule's description for further details.

Which issue(s) this PR fixes:

Fixes #

Special notes for your reviewer:

[loresuso]

cc @incertum @darryk10

[loresuso]

Hello @incertum, thanks for your valuable feedback as usual! Comments addressed

[github-actions[bot]]

Rules files suggestions

falco-incubating_rules.yaml

Comparing 8977ff24cb2c9f12c8334801cb869c7eda97ff0f with latest tag falco-incubating-rules-2.0.0

Minor changes:

• Rule Adding ssh keys to authorized_keys has been added

[poiana]

LGTM label has been added.

Git tree hash: ad9e5641aaa605fa93fe367ea2a1ece9b16c26e7

[poiana]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: darryk10, incertum, loresuso

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Needs approval from an approver in each of these files: - ~~[OWNERS](https://github.com/falcosecurity/rules/blob/main/OWNERS)~~ [incertum] Approvers can indicate their approval by writing `/approve` in a comment Approvers can cancel approval by writing `/approve cancel` in a comment