Since v0.9.0 of BuildKit (BuildX v0.7.0) you can provide a subdirectory
to the default Git context.
Closes#460Closes#528
Signed-off-by: Jim Brännlund <jimbrannlund@fastmail.com>
Fill in title, description and url labels based on the repository information.
Use repository clone URL from `github.event` instead of an undocumented variable.
Fix licenses label to follow SPDX License Expressions.
Signed-off-by: itchyny <itchyny@hatena.ne.jp>