build: print enabled bazel flags on circleci
build: print enabled bazel flags on circleci

We should print all enabled bazel flags on CircleCI. This can help with debugging and
also makes it easier to reproduce CI-specific failures.

josephperrott/material2,mmalerba/material2,mmalerba/material2,Jefiozie/material2,mmalerba/material2,Jefiozie/material2,josephperrott/material2,crisbeto/material2,josephperrott/material2,DevVersion/material2,angular/components,DevVersion/material2,jelbourn/material2,josephperrott/material2,mmalerba/material2,mmalerba/material2,crisbeto/material2,Jefiozie/material2,jelbourn/material2,angular/components,andrewseguin/material2,Jefiozie/material2,josephperrott/material2,Jefiozie/material2,angular/components,andrewseguin/material2,crisbeto/material2,angular/components,andrewseguin/material2,andrewseguin/material2,andrewseguin/material2,jelbourn/material2,jelbourn/material2,jelbourn/material2,DevVersion/material2,DevVersion/material2,DevVersion/material2,crisbeto/material2