Fixes #1776: Removes dummy Test fleet in the webUI #3232

Job	Run time
python-lint	13s
frontend-build	1m 3s
runner-test	53s
gateway-build	0s
runner-compile (linux, amd64, ubuntu-latest)	12s
python-test (macos-latest, 3.8)	2m 38s
python-test (macos-latest, 3.9)	2m 2s
python-test (macos-latest, 3.10)	1m 56s
python-test (macos-latest, 3.11)	1m 55s
python-test (macos-latest, 3.12)	1m 59s
python-test (ubuntu-latest, 3.8)	2m 6s
python-test (ubuntu-latest, 3.9)	4m 3s
python-test (ubuntu-latest, 3.10)	5m 55s
python-test (ubuntu-latest, 3.11)	3m 41s
python-test (ubuntu-latest, 3.12)	4m 2s
python-test (windows-latest, 3.8)	5m 13s
python-test (windows-latest, 3.9)	4m 10s
python-test (windows-latest, 3.10)	5m 50s
python-test (windows-latest, 3.11)	5m 5s
python-test (windows-latest, 3.12)	4m 12s
runner-upload	0s
generate-json-schema	0s
update-get-dstack	0s
	57m 8s

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