fix: fix some warnings when building images

[nayihz]

What this PR does / why we need it

Which issue(s) this PR fixes

Fixes #

There are some warnings when build image.

=> WARN: FromAsCasing: 'as' and 'FROM' keywords' casing do not match (line 5)                                                                   0.0s
=> WARN: InvalidDefaultArgInFrom: Default value for ARG ${BUILDER_IMAGE} results in empty or invalid base image name (line 5)                   0.0s
=> WARN: InvalidDefaultArgInFrom: Default value for ARG ${BASE_IMAGE} results in empty or invalid base image name (line 32)

Special notes for your reviewer

Does this PR introduce a user-facing change?

[kerthcet]

Thanks @nayihz left some comments, not mandatory but part of the project style I think.

[kerthcet]

We use makefile in our project, use Dockerfile directly is not a recommended way, and we don't want to spread the configurations across the project, for example, once the golang version changes, we only need to update the Makefile, which makes more sense to me.

[kerthcet]

So let's not pass the args to the Dockerfile at all. Default it in the Makefile.

[nayihz]

According to the official documentation, it is recommended to set a default value in Dockerfile. Otherwise there will be warning messages.
https://docs.docker.com/reference/build-checks/invalid-default-arg-in-from/#examples

once the golang version changes, we only need to update the Makefile

This is just the default values which only take effect when these parameter is not provided. I think we still could only need to update Makefile in this scenario.

[kerthcet]

/lgtm
/approve

Thanks @nayihz

[kerthcet]

/kind cleanup