lint(hadolint): suppress DL3008 apt pinning, fix WORKDIR warning in full-dev image

Author: ss-o

.trunk/configs/.hadolint.yaml

@@ -1,3 +1,5 @@
 # Following source doesn't work in most setups
 ignored:
   - SC1091
+
+  - DL3008 # Don't pin apt packages to reduce maintenance burden; base image provides stability

docker/full-dev.Dockerfile

@@ -22,7 +22,7 @@ RUN ./Util/preconfig && \
     ./configure --enable-modules --enable-dynamic --with-tcsetpgrp && \
     make -j"$(nproc)" && \
     make install && \
-    cd / && rm -rf /tmp/zsh
+    rm -rf /tmp/zsh
 
 # Set working directory
 WORKDIR /workspace