CI: remove boost from docker image

[edopao]

No description provided.

[github-actions]

Mandatory Tests

Please make sure you run these tests via comment before you merge!

• cscs-ci run default
• cscs-ci run distributed

Optional Tests

To run benchmarks you can use:

• cscs-ci run benchmark-bencher

To run tests and benchmarks with the DaCe backend you can use:

• cscs-ci run dace

To run test levels ignored by the default test suite (mostly simple datatest for static fields computations) you can use:

• cscs-ci run extra

For more detailed information please look at CI in the EXCLAIM universe.

[edopao]

cscs-ci run default

[havogt]

Required for Serialbox as you might have seen. It's not absolutely needed as you can see here, but would be a bit more work to remove it GridTools/serialbox#278