test: add session_worker fixture to step step dependencies test

What was the problem/requirement? (What/Why)

We need the session worker fixture in every WA Job submission test now since otherwise the build will fail with `function uses no fixture operating_system

What was the solution? (How)

Add the worker fixture to the step step dependencies test.

What is the impact of this change?

The test will now pass

How was this change tested?

# Linux
source .e2e_linux_infra.sh
hatch run e2e-test

# Windows
source .e2e_windows_infra.sh
hatch run e2e-test

Was this change documented?

Is this a breaking change?

No

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aws-deadline / deadline-cloud-worker-agent

test: add session_worker fixture to step step dependencies test #432