chore(userspace/falco): make source matching error more expressive

[jasondellaluce]

What type of PR is this?

/kind cleanup

Any specific area of the project related to this PR?

/area engine

What this PR does / why we need it:

Which issue(s) this PR fixes:

Special notes for your reviewer:

Does this PR introduce a user-facing change?:

chore(userspace/falco): make source matching error more expressive

[jasondellaluce]

/milestone 0.36.0

[FedeDP]

/approve

[poiana]

LGTM label has been added.

Git tree hash: 10d33817fa261ecbd43544871ac515d115eade67

[jasondellaluce]

/milestone v0.35.1

[poiana]

@jasondellaluce: The provided milestone is not valid for this repository. Milestones in this repository: [0.35.1, 0.36.0, 0.37.0]

Use /milestone clear to clear the milestone.

In response to this:

/milestone v0.35.1

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes/test-infra repository.

[FedeDP]

/milestone 0.35.1

[Andreagit97]

/approve

[poiana]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: Andreagit97, FedeDP, jasondellaluce

The full list of commands accepted by this bot can be found here.

The pull request process is described here

Needs approval from an approver in each of these files:

• OWNERS [Andreagit97,FedeDP,jasondellaluce]

Approvers can indicate their approval by writing /approve in a comment
Approvers can cancel approval by writing /approve cancel in a comment