fix: Ensure environment is not accessed during a dry run

[arthurpitman]

This PR ensures that no requests are sent to a Dynatrace environment during a dry run by switching to a no-op client early during deployment.

Furthermore, this PR tries to move towards the goal of only having one sort of "clientset" in Monaco, by removing those in from the delete and deploy packages. It also finishes splitting the old DTClient into a classic client and a settings client.

[github-actions[bot]]

Unit Test Results

1 904 tests  ±0   1 903 ✅ ±0   55s ⏱️ - 1m 1s   134 suites ±0       1 💤 ±0      1 files   ±0       0 ❌ ±0 

Results for commit 07c611dc. ± Comparison against base commit 216f434d.

:recycle: This comment has been updated with latest results.

[github-actions[bot]]

E2E Test Results

    4 files  ±0    270 suites  ±0   23m 6s ⏱️ - 4m 45s 2 019 tests ±0  2 017 ✅ ±0  2 💤 ±0  0 ❌ ±0  2 134 runs  ±0  2 132 ✅ ±0  2 💤 ±0  0 ❌ ±0 

Results for commit 07c611dc. ± Comparison against base commit 216f434d.

:recycle: This comment has been updated with latest results.

[sonarcloud[bot]]

Quality Gate passed

Issues
2 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarCloud