component/golang: clear user cache after build

While running tests using all.bash, `$HOME/.cache/go-build/` is
populated with data referencing the build folder. This is problematic
when using shared parts and installing a not pinned software release
multiple times, like it is the case on test node.

A scenario like this can happen:

 - a first succesful build install in `<shared>/golang1.21/<HASH1>`
 - golang1.21 section is changed in a the software release
 - golang1.21 is installed in `<shared>/golang1.21/<HASH2>`, running
   test fails because the cache `<software_folder>/.cache/go-build/` in
   references paths from `<shared>/golang1.21/<HASH1>/.build/go/src`,
   that was used when building the first build and have been removed
   while installing.

This is visible with errors like this:

    2024-03-21 20:52:37,214 INFO     slapgrid_sr: 2024-03-21 20:52:37 slapos[23849] INFO vet: can't parse raw cgo file: open ../../../../a984f246a1b2789081965ab5c05674a8/.build/go/src/net/cgo_linux.go: no such file or directory