FIO-9908: fixed an issue where condition does not work properly if 'show' setting is a string

[TanyaGashtold]

Link to Jira Ticket

https://formio.atlassian.net/browse/FIO-9908

Description

What changed?

If the 'show' setting of conditionals is a string, we need to parse it and convert to boolean so that it works as expected.

Dependencies

formio/core#232
https://github.com/formio/premium/pull/386

How has this PR been tested?

Manually + autotests

Checklist:

• I have completed the above PR template
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation (if applicable)
• My changes generate no new warnings
• My changes include tests that prove my fix is effective (or that my feature works as intended)
• New and existing unit/integration tests pass locally with my changes
• Any dependent changes have corresponding PRs that are listed above