Fix placement of image attribution & customize button when showing the NTP SI Clickbox

[fallaciousreasoning]

Resolves brave/brave-browser#29246

@LaurenWags looking into this I noticed that removing the Stats widget also looks a little weird (it pushes the other widgets lower). I was wondering if this is intentional though, as it looks like it's been around a bit longer than this issue.

Screenshot, with Clock:

Screenshot, without Clock:

note: The red borders are only present in the screenshots.

Submitter Checklist:

• I confirm that no security/privacy review is needed, or that I have requested one
• There is a ticket for my issue
• Used Github auto-closing keywords in the PR description above
• Wrote a good PR/commit description
• Squashed any review feedback or "fixup" commits before merge, so that history is a record of what happened in the repo, not your PR
• Added appropriate labels (QA/Yes or QA/No; release-notes/include or release-notes/exclude; OS/...) to the associated issue
• Checked the PR locally:
  • npm run test -- brave_browser_tests, npm run test -- brave_unit_tests wiki
  • npm run lint, npm run presubmit wiki, npm run gn_check, npm run tslint
• Ran git rebase master (if needed)

Reviewer Checklist:

• A security review is not needed, or a link to one is included in the PR description
• New files have MPL-2.0 license header
• Adequate test coverage exists to prevent regressions
• Major classes, functions and non-trivial code blocks are well-commented
• Changes in component dependencies are properly reflected in gn
• Code follows the style guide
• Test plan is specified in PR before merging

After-merge Checklist:

• The associated issue milestone is set to the smallest version that the
  changes has landed on
• All relevant documentation has been updated, for instance:
  • https://github.com/brave/brave-browser/wiki/Deviations-from-Chromium-(features-we-disable-or-remove)
  • https://github.com/brave/brave-browser/wiki/Proxy-redirected-URLs
  • https://github.com/brave/brave-browser/wiki/Fingerprinting-Protections
  • https://github.com/brave/brave-browser/wiki/Brave%E2%80%99s-Use-of-Referral-Codes
  • https://github.com/brave/brave-browser/wiki/Custom-Headers
  • https://github.com/brave/brave-browser/wiki/Web-Compatibility-Exceptions-in-Brave
  • https://github.com/brave/brave-browser/wiki/QA-Guide
  • https://github.com/brave/brave-browser/wiki/P3A

Test Plan:

See issue

[brave-builds]

A Storybook has been deployed to preview UI for the latest push

[simonhong]

Whenever I test css properties, I fall in love with dev tools :)

[LaurenWags]

Verified with

Brave | 1.51.65 Chromium: 112.0.5615.39 (Official Build) nightly (x86_64)
-- | --
Revision | a0e7b9718a92bcd1cf33b7c95316caff3fc20714-refs/branch-heads/5615@{#753}
OS | macOS Version 12.6.3 (Build 21G419)

Verified steps from brave/brave-browser#29246 (comment).
Confirmed Customize, Settings, etc are properly placed when there are no widgets displayed on NTP SI.

All Widgets Shown	No Widgets Shown

Confirmed Customize, Settings, etc are properly placed when one widget at a time is shown on NTP SI.

Example	Example	Example	Example

Confirmed Customize, Settings, etc are properly placed when different combinations of widgets are shown on NTP SI (not all combinations pictured, just a few).

Example	Example	Example	Example