Add processors and tags to all system data streams

[fearful-symmetry]

What does this PR do?

Fix for #2865
This adds a little drop-down config that adds processors and tags fields to all events in the system integration.

Checklist

• I have reviewed tips for building integrations and this pull request is aligned with them.
• I have verified that all data streams collect metrics or logs.
• I have added an entry to my package's changelog.yml file.
• I have verified that Kibana version constraints are current according to guidelines.

[elasticmachine]

Pinging @elastic/elastic-agent-data-plane (Team:Elastic-Agent-Data-Plane)

[elasticmachine]

💚 Build Succeeded

the below badges are clickable and redirect to their specific view in the CI or DOCS

Expand to view the summary

Build stats

• Start Time: 2022-06-22T18:23:44.309+0000

• Duration: 17 min 13 sec

Test stats 🧪

Test	Results
Failed	0
Passed	270
Skipped	0
Total	270

🤖 GitHub comments

To re-run your PR in the CI, just comment with:

• /test : Re-trigger the build.

[elasticmachine]

🌐 Coverage report

Name	Metrics % (covered/total)	Diff
Packages	100.0% (3/3)	💚
Files	100.0% (4/4)	💚 3.432
Classes	100.0% (4/4)	💚 3.432
Methods	59.74% (46/77)	👎 -29.169
Lines	98.782% (2676/2709)	👍 8.836
Conditionals	100.0% (0/0)	💚

[cmacknz]

Seems a little weird to link to the filebeat processor documentation for an agent feature, but we do it everywhere in integrations it seems.