restore dockerfile to not use go mod cache

Dockerfile

 # NOTE: USING THIS IMAGE UNTIL registry1 credentials are added to IL2 runners
 # Build the manager binary
 FROM registry.il2.dso.mil/platform-one/devops/pipeline-templates/valkyrie/golang-builder-1.16:1.1 as builder
-
+# note: Adam tried to use GOMODCACHE env variable to pull in go cache 
+#       it worked locally but not with buildah.
 WORKDIR /workspace
-# set go module cache
-ENV GOMODCACHE=/workspace/.gomodcache
 # Copy the Go Modules manifests
-COPY . .
+COPY go.mod go.sum ./
+COPY main.go main.go driver.go driver.go ./
+COPY apis/ apis/
+COPY config/ config/
+COPY custom/ custom/
+COPY controllers/ controllers/
+COPY clients/ clients/
 # RUN chmod 755 go.sum
 # download with json logging
 # RUN go mod download -json
 RUN go mod download
 
-# RUN ls -al 
-
 # Build
 RUN CGO_ENABLED=0 GOOS=linux GOARCH=amd64 GO111MODULE=on go build -a -o manager main.go driver.go