Update dependabot schedule

apple/pkl-spring#80 mergedmixed

What it touches

ci: 4 build: 1

Modules: .github (4), gradle (1)

Architectural impact (arcade-agent diff_impact)

No production Java file of this PR maps into the dependency graph (tests, build, CI or docs only). Tests are excluded from the graph by design.

Build & CI relevance

• Touches Gradle/build files: review for build-time or cache impact.
• Touches CI workflows: review runner matrix, timeouts, caching.

Files