upgrading to go 1.21 (#2235)

* chore: bump go to version 1.21

update all depedencies as well

* fix linting issues based on golang 1.20 deprecations

* cleanup go depedencies

* add custom gomega matcher for option intefaces

* revert and upgrade golangci-lint to 1.55.2

* fix lint issues for v1.55.2 of golangci-lint

* fix toml loading test

* remove second runspecs call

* update go.sum

* revert testutil package