Invalid path for api-docs.yaml in full documentation

[dominicboeck]

Hello, I noticed a small inconsistency in the documentation.

The full documentation found at https://springdoc.org/ mentions /v3/api-docs.yml in several places for accessing the API documentation in yaml format. However, the actual path should be /v3/api-docs.yaml as stated in the README. Trying to access /v3/api-docs.yml returns the Whitelabel Error page, while /v3/api-docs.yaml actually downloads the expected API documentation in yaml format.