component/replication-manager: pin golang to 1.16

when using golang 1.17 build fail with errors like:

    github.com/jacobsa/fuse/internal/buffer.memclr: relocation target runtime.memclrNoHeapPointers not defined for ABI0 (but is defined for ABIInternal)
3 jobs for fix/powerdns-system-gcc
Status Job ID Name Coverage
  External
failed SlapOS.SoftwareReleases.IntegrationTest-Master.Python2

failed SlapOS.SoftwareReleases.IntegrationTest-Master.Python3

passed Wendelin.StandaloneDeploymentScriptTest-Debian.Buster.Master