v0.5.0: expression optimizations

• Key changes:
  • Added support for automatic expression optimizations for non-full access requests;
• Minor changes:
  • lfgw:
    • Slight improvements in code style;
    • Migrated to go 1.17;
    • Fully deprecated non-OIDC modes;
    • Bumped go.mod deps;
    • Updated base images;
    • Enabled more linters for golangci-lint;
  • CI:
    • Simplified Taskfile;
    • Enabled dependabot alerts;
    • Added a workflow to publish docker images.