Support Locust >=1

[thilp]

Adds support for the new major version of Locust (locust=~1) in generated locustfiles.

Related to #69.

Description

In generated locustfiles, detect the major version of the corresponding locust package; if that version is 1:

1. Import the new Locust classes instead of the old ones, and create aliases so that most of the rest of the locustfile can stay unchanged.
2. In the definition of our subclass of HttpUser, create a tasks field instead of the task_set field (that triggers a deprecation warning in 1.0).

Types of Changes

What types of changes does your code introduce? Keep the ones that apply:

• Bug fix (non-breaking change which fixes an issue)

TODO

List of tasks you will do to complete the PR:

• Create an alpha release with these changes.
• Get feedback on the alpha release from users.
• When the feedback is positive, bump the version to 1.3.0 and merge this PR to create a new release.

Review

Reviewers' checklist:

• If this PR implements new flows or changes existing ones, are there
  good tests for these flows?
  If this PR rather removes flows, are the obsolete tests removed as well?
• Is the documentation still up-to-date and exhaustive? This covers both
  technical (in source files) and functional (under docs/) documentation.
• Is the changelog updated?
• Does the new version number correspond to the actual changes from this PR?
  In doubt, refer to https://semver.org.

[zincr]

🤖 zincr found 0 problems , 1 warning

ℹ️ Large Commits
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✅ Dependency Licensing

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Large Commits

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This file contains a substantial change, please review to determine if the change comes from an external source and if there are any copyright or licensing issues to be aware of

• ℹ️ poetry.lock had +100 lines of code changed in a single commit
  Please review this file to determine the source of this change
   

[tortila]

Interesting approach with the aliases. I like how little code needs to be changed because of it!

[thilp]

Thank you 😊