fix: remove preconfigured policies from 7.15

[mdelapenya]

What does this PR do?

As per @nchaulet's comment in #1680 (comment), preconfigured policies should not be present in 7.15

This PR is removing the examples we created as placeholders for that feature in master, that were backported as part of #1644

Why is it important?

Those scenarios should not be run on CI, which is causing noise in the nightly scheduled build for 7.15

Checklist

• My code follows the style guidelines of this project
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• I have made corresponding change to the default configuration files
• I have added tests that prove my fix is effective or that my feature works
• I have run the Unit tests (make unit-test), and they are passing locally
• I have run the End-2-End tests for the suite I'm working on, and they are passing locally
• I have noticed new Go dependencies (run make notice in the proper directory)

How to test this PR locally

Running this command should return 0 scenarios:

TAGS="@policies" TIMEOUT_FACTOR=3 LOG_LEVEL=TRACE DEVELOPER_MODE=true ELASTIC_APM_ACTIVE=false PROVIDER=elastic-package  make -C e2e/_suites/fleet functional-test

Related issues

• Relates Test preconfigured agent policies and output  #1680
• Relates feat: support running kibana with different configs #1644

[elasticmachine]

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Build stats

• Start Time: 2021-11-04T06:50:02.354+0000

• Duration: 44 min 37 sec

• Commit: 54b0353

Test stats 🧪

Test	Results
Failed	0
Passed	237
Skipped	0
Total	237

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