feature: change example to use non-root (#1879)

#### What type of PR is this?

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Add one of the following kinds:
/kind bug
/kind cleanup
/kind documentation
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/kind feature

#### What this PR does / why we need it:

This changes our example to use non-root so it runs well on non-root
clusters (ex. openshift).

We also add debugging tools so we can safely explore the container.

/tmp is also added as the directory for the replica or else it fails.

#### Which issue(s) this PR fixes:
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*Automatically closes linked issue when PR is merged.
Usage: `Fixes #<issue number>`, or `Fixes (paste link of issue)`.
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N/A

#### Special notes for your reviewer:

Signed-off-by: Charlie Drage <charlie@charliedrage.com>

examples/compose.yaml

@@ -2,16 +2,16 @@ services:
 
   redis-leader:
     container_name: redis-leader
-    image: redis:latest
+    image: redis
     ports:
       - "6379"
 
   redis-replica:
     container_name: redis-replica
-    image: redis:latest
+    image: redis
     ports:
       - "6379"
-    command: redis-server --replicaof redis-leader 6379
+    command: redis-server --replicaof redis-leader 6379 --dir /tmp
 
   web:
     container_name: web

examples/web/Dockerfile

@@ -1,4 +1,9 @@
 FROM golang:1.21.2
+
+# Debugging within the container
+RUN apt-get update && apt-get install dnsutils redis-tools -y
+
+# Set the working directory in the container
 WORKDIR /app
 
 # Copy the entire project which includes the public directory, vendoring, etc.
@@ -7,5 +12,15 @@ COPY . .
 # Build your application
 RUN CGO_ENABLED=0 GOOS=linux go build -o /frontend
 
+# Change the permissions so that all users can execute it
+RUN chmod +x /frontend
+
+# Although setting permissions on /frontend should suffice, set wider permissions if needed
+RUN chown -R 1001:0 /app && \
+    chmod -R g=u /app
+
+# This directive ensures the container does not run as root
+USER 1001
+
 EXPOSE 8080
 CMD ["/frontend"]