chore: remove redundant "make fix" tools

Description

gofumpt is enabled in golangci-lint, and is a gofmt superset, so no need to run gofmt separately. gofumpt also simplifies by default (and unconditionally), so no need to configure anything related to that bit. Ref https://github.com/mvdan/gofumpt#added-rules

goimports is also enabled in golangci-lint, so drop the separate superfluous run of it.

Related Issues

N/A

How has this been tested?

Manually, running make fix.

Screenshots (if appropriate):

N/A