Dockerfile hadolint fixes, part 2 (PlummersSoftwareLLC#744)

Author: Macleykun

PrimeClipper/solution_1/Dockerfile

@@ -12,10 +12,10 @@ RUN apt-get update && \
     rm -rf /var/lib/apt/lists/* && \
     rm "${HARBOUR_PKG}" 
 
-COPY . /opt/
+COPY . .
 
-RUN hbmk2 -gtstd -optim -cflag=-O3 ./sieve.prg
-RUN hbmk2 -gtstd -optim -cflag=-O3 ./sievedb.prg
-RUN hbmk2 -gtstd -optim -cflag=-O3 ./sieve_xharbour.prg
+RUN hbmk2 -gtstd -optim -cflag=-O3 ./sieve.prg \
+    && hbmk2 -gtstd -optim -cflag=-O3 ./sievedb.prg \
+    && hbmk2 -gtstd -optim -cflag=-O3 ./sieve_xharbour.prg
 
 CMD [ "bash", "./run.sh" ]

PrimeCrystal/solution_2/Dockerfile

@@ -4,7 +4,10 @@ ENV CRYSTAL_VER="1.1"
 
 WORKDIR /opt
 
-RUN apt-get update && apt-get upgrade -y && apt-get install -y curl && \
+SHELL ["/bin/bash", "-o", "pipefail", "-c"]
+RUN apt-get update && apt-get install -y curl && \
+    apt-get clean && \
+    rm -rf /var/lib/apt/lists/* && \
     curl -fsSL https://crystal-lang.org/install.sh | bash -s -- --version="${CRYSTAL_VER}"
 # compiler build has been finished here, image ready for use...