Update dependency vega-lite to v5.15.1

[renovate]

This PR contains the following updates:

Package	Change	Age	Adoption	Passing	Confidence
vega-lite (source)	5.15.0 -> 5.15.1

---

Release Notes

vega/vega-lite (vega-lite)

v5.15.1

Compare Source

Bug Fixes

• correct the formula for interpolating between bin start and end (interpolatedSignalRef) (#​9111) (d4b27bb)
• use resolve "shared" instead of steps to fix artifacts in grouped density transform (#​9106) (06e63e6)

---

Configuration

📅 Schedule: Branch creation - At any time (no schedule defined), Automerge - At any time (no schedule defined).

🚦 Automerge: Disabled by config. Please merge this manually once you are satisfied.

♻ Rebasing: Whenever PR becomes conflicted, or you tick the rebase/retry checkbox.

🔕 Ignore: Close this PR and you won't be reminded about this update again.

---

• If you want to rebase/retry this PR, check this box

---

This PR has been generated by Mend Renovate. View repository job log here.

[codecov]

Codecov Report

Merging #185 (a166d63) into master (bbe0dfd) will not change coverage.
The diff coverage is n/a.

@@            Coverage Diff            @@
##            master      #185   +/-   ##
=========================================
  Coverage   100.00%   100.00%           
=========================================
  Files            8         8           
  Lines          401       401           
  Branches        76        76           
=========================================
  Hits           401       401           

📣 We’re building smart automated test selection to slash your CI/CD build times. Learn more