pip: DeathReaper install wrongly placed in build process (#498)

Found extra and wildcard specifications solution thanks to:
https://stackoverflow.com/a/76902327

image/pip

@@ -18,7 +18,7 @@ RUN poetry install --only main --no-root
 
 # Copy source tree, install and build Silkaj
 COPY ./ ./
-RUN poetry install --only main --extras deathreaper
+RUN poetry install --only main
 RUN poetry build
 
 # ------------------------------------------------------------------------------
@@ -40,7 +40,7 @@ RUN apt update && \
 
 # Copy the build artifact from the build stage
 COPY --from=build "/silkaj/dist/silkaj-*-py3-none-any.whl" .
-RUN pip install silkaj-*-py3-none-any.whl
+RUN pip install silkaj[deathreaper] silkaj-*-py3-none-any.whl
 
 # Use silkaj user
 USER silkaj