Replace formation-override label styles with USWDS import

[jamigibbs]

Description

In Formation, the .usa-labels class was being imported directly from USWDS v1. We have temporarily ported those styles over to the CSS-Library in the /formation-overrides folder and now we would like it instead to be imported from the USWDS v3 module.

Tasks

• Remove the /stylesheets/formation-overrides/elements/labels.scss file.
• Import the USWDS usa-label package (Discuss with the team about CSS-Library organization if necessary)
• Test the CSS-Library in vets-website to make sure that the .usa-labels class still works and note if there are any visual changes between the v1 and v3 version.

Acceptance Criteria

• The .usa-labels class still works abd it is being imported directly from the USWDS v3 package.

[caw310]

Please add your estimate of 1, 2, 3, 5, 8 or 13
@Andrew565 - 3
@ataker - 3
@harshil1793
@it-harrison - 3
@jamigibbs - 3
@micahchiang - 3
@powellkerry - 3
@rmessina1010 - 5
@rsmithadhoc - 3

[powellkerry]

This ticket depends on completion of #3621 and #3602