react-core Select creates nested form

[kahboom]

For some reason, PF wraps Select in a form element, which is causing issues, as you're not really supposed to nest forms. This doesn't happen with FormSelect, which uses a normal <select> tag, but I need to use Select because it has the isCreatable option.. it seems like it was introduced in this PR: https://github.com/patternfly/patternfly-react/pull/2820/files#diff-fd84af25e09f77329b1e8c8fd1d08914R406

If you try to use Select within a Formik form, you can get errors like this:
Warning: validateDOMNesting(...): <form> cannot appear as a descendant of <form>

I am trying this workaround for a Formik custom widget I created, but it's not going so well as we are generating forms automatically based on backend-provided values and have no control over how they get rendered: jaredpalmer/formik#826 (comment)

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For feature requests or enhancements, file an issue against patternfly-design.

For bug reports, please provide as much relevant info as possible:

• What browser(s), device and OS experience the problem? Chrome, macOS Catalina
• Are you using a PatternFly JS framework implementation [1]? Yes, patternfly-react v3.120.8
• What are the steps to reproduce the issue and what is the expected behavior? For the the fastest support, provide a working demo or minimal reproduction using tools such as codepen or jsfiddle

Tell us more about your product/project and timeline to help prioritize this issue.

• What product/project does this impact? Fuse Online + Syndesis
• List product/project release(s) and timelines. Deadline was Monday, bug fixing now
• Is this a customer reported blocking issue? No