fix: update Dockerfile to use Alpine base image and add cleanup script for droplet management

orchestrator/Dockerfile

@@ -1,12 +1,8 @@
-FROM catthehacker/ubuntu:runner-22.04
-USER root
-RUN apt-get update && apt-get install -y curl bash git wget openssh-client
-
-RUN wget https://github.com/digitalocean/doctl/releases/download/v1.141.0/doctl-1.141.0-linux-amd64.tar.gz \
-    && tar -xvf doctl-1.141.0-linux-amd64.tar.gz \
-    && mv doctl /usr/local/bin \
-    && rm doctl-1.141.0-linux-amd64.tar.gz
+FROM alpine:latest
+RUN apk add --no-cache curl bash git doctl openssh
 
 COPY orchestrating.sh /usr/local/bin/orchestrating
 COPY cleanup.sh /usr/local/bin/cleanup
 RUN chmod 755 /usr/local/bin/orchestrating /usr/local/bin/cleanup
+
+RUN mkdir -p /var/run/act/