Allow passing arguments to bazel build

[jamielennox]

To make a container capable of being used by skaffold I need to be able
to provide additional parameters on the command line. Add an args:
element to the bazel build configuration that is a list of strings that
will be passed to the build command.

[jamielennox]

My specific requirement here is that I'm running bazel on OSX with a golang codebase. There are a couple of problems to do with the toolchain, gazelle, that don't resolve dependencies correctly when simply specify cross compile parameters. The advice from bazel is to pass "--platforms=@io_bazel_rules_go//go/toolchain:linux_amd64" to the build process.

This will provide a way to set these parameters.

[codecov-io]

Codecov Report

Merging #1289 into master will decrease coverage by 0.02%.
The diff coverage is 0%.

@@            Coverage Diff             @@
##           master    #1289      +/-   ##
==========================================
- Coverage   44.24%   44.21%   -0.03%     
==========================================
  Files         104      104              
  Lines        4629     4632       +3     
==========================================
  Hits         2048     2048              
- Misses       2372     2375       +3     
  Partials      209      209

Impacted Files	Coverage Δ
pkg/skaffold/build/local/bazel.go	0% <0%> (ø)	⬆️

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