chore: switch base image from distroless to alpine (#67)

## This PR

- switch base image from distroless to alpine

### Notes

The Alpine image makes it much easier to mount local volumes. It's also
used in many other popular CLI as a base image.

### How to test

Build locally and run the container.

Signed-off-by: Michael Beemer <[email protected]>

Dockerfile

@@ -1,7 +1,7 @@
-# Use distroless as minimal base image to package the manager binary
-# Refer to https://github.com/GoogleContainerTools/distroless for more details
-FROM gcr.io/distroless/static:nonroot
-COPY ./openfeature-cli /openfeature-cli
-USER 65532:65532
+FROM alpine:3.21
 
-ENTRYPOINT ["/openfeature-cli"]
+COPY ./openfeature-cli usr/local/bin/openfeature-cli
+
+RUN chmod +x /usr/local/bin/openfeature-cli
+
+ENTRYPOINT ["/usr/local/bin/openfeature-cli"]