(fix) : Makefile docker build command by removing platform-specific setup

- Updated `docker-build` to remove platform-specific configurations, making it architecture-agnostic.
- The command now builds according to the local environment's architecture without specifying `GOOS` or `GOARCH`.
- Simplifies the Makefile by removing unnecessary exports for platform-specific builds, allowing compatibility across both Linux and macOS without manual adjustments.

Note that when we run `make docker-build` it is not working.
It fails with the error:

```
Error:
) $ make build docker-build
/Users/camiladeomacedo/go/bin/controller-gen-v0.16.1 rbac:roleName=manager-role crd webhook paths="./..." output:crd:artifacts:config=config/base/crd/bases output:rbac:artifacts:config=config/base/rbac
/Users/camiladeomacedo/go/bin/controller-gen-v0.16.1 object:headerFile="hack/boilerplate.go.txt" paths="./..."
go fmt ./...
go vet -tags 'containers_image_openpgp' ./...
```

This change ensures that the docker build will build the binary according to the local architecture and not for a specific ARCH. It simplifies the Makefile and logic to build.

Author: camilamacedo86

Makefile

@@ -269,19 +269,12 @@ build: build-deps go-build-local #HELP Build manager binary for current GOOS and
 go-build-local: BUILDBIN := bin
 go-build-local: $(BINARIES)
 
-.PHONY: build-linux go-build-linux
-build-linux: build-deps go-build-linux #EXHELP Build manager binary for GOOS=linux and local GOARCH.
-go-build-linux: BUILDBIN := bin/linux
-go-build-linux: export GOOS=linux
-go-build-linux: export GOARCH=amd64
-go-build-linux: $(BINARIES)
-
 .PHONY: run
 run: docker-build kind-cluster kind-load kind-deploy #HELP Build the operator-controller then deploy it into a new kind cluster.
 
 .PHONY: docker-build
-docker-build: build-linux #EXHELP Build docker image for operator-controller with GOOS=linux and local GOARCH.
-	$(CONTAINER_RUNTIME) build -t $(IMG) -f Dockerfile ./bin/linux
+docker-build: build #EXHELP Build the operator-controller manager with local GOOS/GOARCH
+	$(CONTAINER_RUNTIME) build -t $(IMG) -f Dockerfile ./bin/
 
 #SECTION Release
 ifeq ($(origin ENABLE_RELEASE_PIPELINE), undefined)