feat: improves ValidateContextDirectory performance
feat: improves ValidateContextDirectory performance

Signed-off-by: Nao YONASHIRO <a6eb875041ff1aa3ba9f5cec4196391c0c6688f7@gmail.com>

cpuguy83/cli,thaJeztah/cli,thaJeztah/cli,docker/cli,docker/cli,cpuguy83/cli