refactor(ios): update toolbar and tabbar default background colors

[liamdebeasi]

Starters: ionic-team/starters#1670
Docs: ionic-team/ionic-docs#1835

Pull request checklist

Please check if your PR fulfills the following requirements:

• Tests for the changes have been added (for bug fixes / features)
• Docs have been reviewed and added / updated if needed (for bug fixes / features)
• Build (npm run build) was run locally and any changes were pushed
• Lint (npm run lint) has passed locally and any fixes were made for failures

Pull request type

Please check the type of change your PR introduces:

• Bugfix
• Feature
• Code style update (formatting, renaming)
• Refactoring (no functional changes, no api changes)
• Build related changes
• Documentation content changes
• Other (please describe):

What is the current behavior?

Issue Number: resolves#22780

What is the new behavior?

• Updated toolbar and tab bar default background colors (fallback values)

Does this introduce a breaking change?

• Yes
• No

Other information

[liamdebeasi]

Large Title

Light - Collapsed toolbar has changed from white to light gray
Dark - No changes

	before	after
light
dark

Toolbar

Light - Header and footer toolbars have changed from white to light gray
Dark - No changes

	before	after
light
dark

Tabbar

Light - Tab bar background has changed from white to light gray
Dark - Tab bar background has changed from black to dark gray

	before	after
light
dark