Change build order and add modifytags tool

.devcontainer/Dockerfile

@@ -10,28 +10,6 @@ ENV DEBIAN_FRONTEND=noninteractive
 RUN apt-get update \
     && apt-get -y install --no-install-recommends apt-utils 2>&1
 
-RUN go get -u -v \
-    github.com/mdempsky/gocode \
-    github.com/uudashr/gopkgs/cmd/gopkgs \
-    github.com/ramya-rao-a/go-outline \
-    github.com/acroca/go-symbols \
-    github.com/godoctor/godoctor \
-    golang.org/x/tools/cmd/guru \
-    golang.org/x/tools/cmd/gorename \
-    github.com/rogpeppe/godef \
-    github.com/zmb3/gogetdoc \
-    github.com/sqs/goreturns \
-    github.com/josharian/impl \
-    github.com/davidrjenni/reftools/cmd/fillstruct \
-    golang.org/x/tools/cmd/goimports \
-    golang.org/x/lint/golint \
-    golang.org/x/tools/cmd/gopls \
-    github.com/alecthomas/gometalinter \
-    honnef.co/go/tools/... \
-    github.com/golangci/golangci-lint/cmd/golangci-lint \
-    github.com/mgechev/revive \
-    github.com/derekparker/delve/cmd/dlv 2>&1
-
 # gocode-gomod
 RUN go get -x -d github.com/stamblerre/gocode 2>&1 \
     && go build -o gocode-gomod github.com/stamblerre/gocode \
@@ -48,3 +26,27 @@ ENV DEBIAN_FRONTEND=dialog
 
 # Set the default shell to bash rather than sh
 ENV SHELL /bin/bash
+
+# go tools
+RUN go get -u -v \
+    github.com/mdempsky/gocode \
+    github.com/uudashr/gopkgs/cmd/gopkgs \
+    github.com/ramya-rao-a/go-outline \
+    github.com/acroca/go-symbols \
+    github.com/godoctor/godoctor \
+    golang.org/x/tools/cmd/guru \
+    golang.org/x/tools/cmd/gorename \
+    github.com/rogpeppe/godef \
+    github.com/zmb3/gogetdoc \
+    github.com/sqs/goreturns \
+    github.com/josharian/impl \
+    github.com/davidrjenni/reftools/cmd/fillstruct \
+    github.com/fatih/gomodifytags \
+    golang.org/x/tools/cmd/goimports \
+    golang.org/x/lint/golint \
+    golang.org/x/tools/cmd/gopls \
+    github.com/alecthomas/gometalinter \
+    honnef.co/go/tools/... \
+    github.com/golangci/golangci-lint/cmd/golangci-lint \
+    github.com/mgechev/revive \
+    github.com/derekparker/delve/cmd/dlv 2>&1