Configuration files in examples/ are not considered

[ianfixes]

via Arduino-CI/action#17 (comment)

not allowing a configuration file in the ~/examples/ directory, but allowing a file in the ~/tests/directory is inconsistent

This is a fair point. The question is whether to apply platform/package installation rules upon entering examples/ or simply rely on the overridden config at the individual examples level to accomplish it. My initial thought is to ignore the contents of examples/.arduino-ci.yml by itself and focus solely on the subdirectories which may or may not override that.