fix(workflow): adding Dockerfile

misc/docker/Dockerfile

@@ -0,0 +1,18 @@
+# Base image
+FROM golang AS builder
+
+# Set directory to known value
+WORKDIR /app
+# Define the version as a build argument
+ARG GOTEMPLATE_VERSION=3.12.0
+
+# Git clone the repo for gotemplate, checkout the desired tag, and build the executable
+RUN git clone https://github.com/coveooss/gotemplate.git . && \
+    git checkout v${GOTEMPLATE_VERSION} && \
+    CGO_ENABLED=0 go build
+
+FROM busybox
+
+COPY --from=builder /app/gotemplate /gotemplate
+
+ENTRYPOINT [ "/gotemplate" ]