fix: remove .dockerignore to ensure clean version computation

This commit removes the `.dockerignore` file from the repository. The
current build process relies on `git describe` to compute the Kepler
version. However, the `.dockerignore` file was causing certain
Git-tracked files to be excluded from the Docker build context, leading
to `dirty` version state. By removing the `.dockerignore` file, we
ensure that all files are included, allowing Git to recognize a clean
working directory during the image build process

Signed-off-by: Vibhu Prashar <[email protected]>