[wpt] Remove the align-dialog-* tests.

It was resolved to remove the {align,justify}-self:dialog values in:
w3c/csswg-drafts#10258 (comment)

Tests for auto-margin ignoring were added in:
fantasai@e283b4a

Change-Id: I33dd95cb45e05ca7a2cf485a846cbfef22986429
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/7119879
Commit-Queue: Ian Kilpatrick <ikilpatrick@chromium.org>
Reviewed-by: Ian Kilpatrick <ikilpatrick@chromium.org>
Auto-Submit: Ian Kilpatrick <ikilpatrick@chromium.org>
Reviewed-by: David Grogan <dgrogan@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1540163}

Author: bfgeek