Removed call to fleet setup during container start

[michalpristas]

As setup is now called in kibana we don't need to call it at all.
PR removes these calls and ENV variable altering behavior.

Tested:

• enroll modified agent to normal fleet
• enroll modified agent on k8s to normal fleet
• enroll modified agent to cloud instance running modified agent (using cloud first testing)

All working

Fixes: #2910

[elasticmachine]

Pinging @elastic/elastic-agent-control-plane (Team:Elastic-Agent-Control-Plane)

[elasticmachine]

Pinging @elastic/elastic-agent (Team:Elastic-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

• Start Time: 2023-07-04T11:19:04.394+0000

• Duration: 23 min 1 sec

Test stats 🧪

Test	Results
Failed	0
Passed	5935
Skipped	23
Total	5958

💚 Flaky test report

Tests succeeded.

🤖 GitHub comments

Expand to view the GitHub comments

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

• /test : Re-trigger the build.

• /package : Generate the packages.

• run integration tests : Run the Elastic Agent Integration tests.

• run end-to-end tests : Generate the packages and run the E2E Tests.

• run elasticsearch-ci/docs : Re-trigger the docs validation. (use unformatted text in the comment!)

[elasticmachine]

🌐 Coverage report

Name	Metrics % (covered/total)	Diff
Packages	98.684% (75/76)	👍
Files	68.582% (179/261)	👍
Classes	66.94% (326/487)	👍
Methods	54.112% (1033/1909)	👍 0.057
Lines	40.302% (11860/29428)	👍 0.038
Conditionals	100.0% (0/0)	💚

[pchila]

LGTM

[cmacknz]

This is missing a changelog fragment :p

[pierrehilbert]

@michalpristas could you please correct this and add it when you will be back?

[michalpristas]

changelog fragment: #3035