Allow non-optional integer/float params without value attribute

[nsoranzo]

Previously a tool with such an input would fail to load.

Also:

• Add test tool.
• Add some type annotations to ToolParameter methods
• Use super()

How to test the changes?

(Select all options that apply)

• I've included appropriate automated tests.
• This is a refactoring of components with existing test coverage.
• Instructions for manual testing are as follows:
  1. [add testing steps and prerequisites here if you didn't write automated tests covering all your changes]

License

• I agree to license these and all my past contributions to the core galaxy codebase under the MIT license.

[bernt-matthias]

If I have read the code correctly, then bool should already work. For selects we have #9203 (comment)

However for the numeric parameters your fix looks good to me.

[bernt-matthias]

Fixes #16960

[nsoranzo]

The failing Selenium test is unrelated (looks like that lib/galaxy_test/selenium/test_workflow_editor.py::TestWorkflowEditor::test_edit_license is flaky).