Fix UI issues in Applications form

@douwe Thanks for reviewing this small fix.

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Before:

![application_form_before](https://dev.gitlab.org/gitlab/gitlabhq/uploads/11fbee17ad6a4c9456cd7d6cba5ae429/application_form_before.png)

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After:

![application_form_after](https://dev.gitlab.org/gitlab/gitlabhq/uploads/0c64214ccda6c77095f468fcb8c748f3/application_form_after.png)

See merge request !1859