feat: use a library to scan RPM packages instead of an external tool

Upgrade the snyk-docker-plugin dependency which carries @snyk/rpm-parser.
This allows us to scan RPM packages directly instead of shelling out to a tool.

We no longer need to pass a path to a temporary directory for storing extracted files.
Also, we no longer need to build and embed the tool in the Dockerfile.

Author: ivanstanev

Dockerfile

@@ -10,18 +10,7 @@ RUN cd $GOPATH/src/github.com/containers/skopeo \
   && make install
 
 #---------------------------------------------------------------------
-# STAGE 2: Build the go-rpmdb tool.
-#---------------------------------------------------------------------
-FROM golang:1.13.1-alpine3.10 AS rpmdb-build
-
-RUN apk --no-cache add git gcc musl-dev db-dev openssl-dev
-RUN git clone --depth 1 -b 'v1.1.0' https://github.com/snyk/go-rpmdb $GOPATH/src/github.com/snyk/go-rpmdb
-RUN cd $GOPATH/src/github.com/snyk/go-rpmdb \
-    && GIT_COMMIT=$(git rev-parse HEAD 2> /dev/null || true) \
-    && GO111MODULE=on go build -ldflags "-X main.gitCommit=${GIT_COMMIT}" -o rpmdb ./cmd/rpmdb
-
-#---------------------------------------------------------------------
-# STAGE 3: Build the kubernetes-monitor
+# STAGE 2: Build the kubernetes-monitor
 #---------------------------------------------------------------------
 FROM node:erbium-alpine
 
@@ -31,7 +20,7 @@ ENV NODE_ENV production
 
 RUN apk update
 RUN apk upgrade
-RUN apk --no-cache add db dumb-init
+RUN apk --no-cache add dumb-init
 
 RUN addgroup -S -g 10001 snyk
 RUN adduser -S -G snyk -h /srv/app -u 10001 snyk
@@ -43,8 +32,6 @@ COPY --chown=snyk:snyk --from=skopeo-build /usr/bin/skopeo /usr/bin/skopeo
 COPY --chown=snyk:snyk --from=skopeo-build /etc/containers/registries.d/default.yaml /etc/containers/registries.d/default.yaml
 COPY --chown=snyk:snyk --from=skopeo-build /etc/containers/policy.json /etc/containers/policy.json
 
-COPY --chown=snyk:snyk --from=rpmdb-build /go/src/github.com/snyk/go-rpmdb/rpmdb /usr/bin/rpmdb
-
 # Add manifest files and install before adding anything else to take advantage of layer caching
 ADD --chown=snyk:snyk package.json package-lock.json .snyk ./