deps: bump github.com/axw/gocov from 1.1.0 to 1.2.1 in /build/tools (#3068)

Bumps [github.com/axw/gocov](https://github.com/axw/gocov) from 1.1.0 to 1.2.1.
- [Release notes](https://github.com/axw/gocov/releases)
- [Commits](axw/gocov@v1.1.0...v1.2.1)

---
updated-dependencies:
- dependency-name: github.com/axw/gocov
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

build/tools/go.mod

@@ -6,7 +6,7 @@ toolchain go1.23.2
 
 require (
 	github.com/AlekSi/gocov-xml v1.1.0
-	github.com/axw/gocov v1.1.0
+	github.com/axw/gocov v1.2.1
 	github.com/golang/mock v1.6.0
 	github.com/golangci/golangci-lint v1.61.0
 	github.com/jstemmer/go-junit-report v1.0.0
@@ -120,7 +120,6 @@ require (
 	github.com/mattn/go-colorable v0.1.13 // indirect
 	github.com/mattn/go-isatty v0.0.20 // indirect
 	github.com/mattn/go-runewidth v0.0.16 // indirect
-	github.com/matttproud/golang_protobuf_extensions/v2 v2.0.0 // indirect
 	github.com/mgechev/revive v1.4.0 // indirect
 	github.com/mitchellh/go-homedir v1.1.0 // indirect
 	github.com/mitchellh/mapstructure v1.5.0 // indirect
@@ -172,7 +171,6 @@ require (
 	github.com/stretchr/objx v0.5.2 // indirect
 	github.com/stretchr/testify v1.9.0 // indirect
 	github.com/subosito/gotenv v1.6.0 // indirect
-	github.com/t-yuki/gocover-cobertura v0.0.0-20180217150009-aaee18c8195c // indirect
 	github.com/tdakkota/asciicheck v0.2.0 // indirect
 	github.com/tetafro/godot v1.4.18 // indirect
 	github.com/timakin/bodyclose v0.0.0-20240125160201-f835fa56326a // indirect