Refactor default value for select (#5343)

In this PR, we are refactoring two things:
- leverage field.defaultValue for Select and MultiSelect settings form
(instead of option.isDefault)
- use quoted string (ex: "'USD'") for string default values to embrace
backend format

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Co-authored-by: Thaïs Guigon <guigon.thais@gmail.com>

packages/twenty-ui/__mocks__/imageMock.js

@@ -0,0 +1 @@
+export default 'test-file-stub';