Filters should be grouped using a <fieldset> and <legend> markup

[laflannery]

Description

Related field elements in the same form should be grouped together using a <fieldset> and <legend> markup. This allows sreen readers users to hear the context of each field as the go through the form.

For example, in the case of the search filter, if a legend were added of "Find a VA location", when they would hear "Service type, Find a VA location" when they tabbed to that particular select field.

Acceptance Criteria

• <fieldset> wraps all form elements
• Appropriate <legend> is added
• Screen reader announces Legend for each form field

[laflannery]

@thejordanwood can we also add this as annotations? Once we get the final filters confirmed I think this, as well as probably some other notes and directions would be helpful to ensure proper implementation

[kmariepat-cityfriends]

Will hold on implementing until #11542 is complete OR in progress

[laflannery]

Closing in favor of #14913