tests: Resolve warnings by removing scheduler and updating arguments

[EwoutH]

This PR updates several test files to resolve warnings and deprecations introduced in Mesa 3.0. The changes align the tests with the new AgentSet functionality and the removal of schedulers.

Changes

1. Remove scheduler from batch_run tests

The schedule parameter and related code were removed from the MockModel in test_batch_run.py. This aligns with the deprecation of schedulers in favor of AgentSet functionality.

Example:

# Old
self.schedule = BaseScheduler(self) if schedule is None else schedule
self.schedule.add(MockAgent(self, agent_val))

# New
MockAgent(self, agent_val)

Related PR: #1926

2. Remove scheduler from datacollector tests

The schedule attribute and related methods were removed from the MockModel in test_datacollector.py. The step method now uses self.agents.do("step") instead of self.schedule.step().

Example:

# Old
self.schedule = BaseScheduler(self)
self.schedule.step()

# New
self.agents.do("step")

Related PR: #1926

3. Replace n with at_most in AgentSet select

In test_agent.py, the deprecated n parameter in AgentSet.select() was replaced with at_most.

Example:

# Old
agentset.select(test_function, n=2)

# New
agentset.select(test_function, at_most=2)

Related PR: #2253

4. Replace scheduler in lifespan tests

In test_lifespan.py, the RandomActivation scheduler was removed, and the step method now uses self.agents.shuffle_do("step"). The order of stepping and data collection was also adjusted to align with the new structure.

Example:

# Old
self.schedule = RandomActivation(self)
self.schedule.step()
self.datacollector.collect(self)

# New
self.agents.shuffle_do("step")
self.datacollector.collect(self)

Related PR: #1926

5. Rename Agent classes to not start with Test

Agent classes in test files were renamed to avoid starting with "Test" to prevent confusion with test methods.

Example:

# Old
class TestAgent(Agent):

# New
class AgentTest(Agent):

This change improves clarity and adheres to common naming conventions for test classes.

Summary

These updates resolve warnings and deprecations introduced in Mesa 3.0, particularly related to the removal of schedulers and the new AgentSet functionality. The changes ensure that our tests are up-to-date with the latest Mesa API and best practices.

[github-actions]

Performance benchmarks:

Model	Size	Init time [95% CI]	Run time [95% CI]
BoltzmannWealth	small	🔵 -1.0% [-2.0%, -0.1%]	🔵 +0.2% [-0.1%, +0.6%]
BoltzmannWealth	large	🔵 -0.7% [-1.4%, -0.0%]	🔵 -1.1% [-1.8%, -0.4%]
Schelling	small	🔵 -1.2% [-1.7%, -0.6%]	🔵 -0.8% [-1.3%, -0.3%]
Schelling	large	🔵 -1.0% [-2.1%, -0.1%]	🔵 -1.4% [-2.1%, -0.7%]
WolfSheep	small	🔵 +0.0% [-0.4%, +0.5%]	🔵 +0.6% [+0.4%, +0.8%]
WolfSheep	large	🔵 +2.3% [+0.3%, +4.4%]	🔵 +5.2% [+2.1%, +8.4%]
BoidFlockers	small	🔵 +1.4% [+0.8%, +2.1%]	🔵 +1.3% [+0.6%, +1.9%]
BoidFlockers	large	🔵 +2.3% [+1.2%, +3.8%]	🔵 +0.8% [+0.4%, +1.2%]

[EwoutH]

Done, this PR resolves almost all open warnings in the tests.