Fix issues in docker build #664
Description
2 warnings found (use docker --debug to expand):
- FromAsCasing: 'as' and 'FROM' keywords' casing do not match (line 2)
- LegacyKeyValueFormat: "ENV key=value" should be used instead of legacy "ENV key value" format (line 3)
See: https://github.com/oasdiff/oasdiff/actions/runs/13762347885/job/38481066101