Remove fleet datastream bootstrap

[aleksmaus]

What does this PR do?

Removes .fleet-actions-results datastream bootstrapping from fleet_server package.
Tested with local package registry and ES PR changes.

The ES change PR is still in review: elastic/elasticsearch#71667

DO NOT MERGE! until ES PR is merged and ES docker images are published

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.

Related issues

• Relates Add Fleet action results system data stream elasticsearch#71667

Screenshots

[elasticmachine]

Pinging @elastic/agent (Team:Agent)

[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

• Build Cause: Branch indexing

• Start Time: 2021-04-20T22:28:20.194+0000

• Duration: 50 min 42 sec

• Commit: c2640cf

Test stats 🧪

Test	Results
Failed	0
Passed	1926
Skipped	3
Total	1929

Trends 🧪