Update Dockerfile

Author: object-Object

.github/.devcontainer/Dockerfile

@@ -36,7 +36,7 @@ RUN SNIPPET="export PROMPT_COMMAND='history -a' && export HISTFILE=/commandhisto
     && touch /commandhistory/.bash_history \
     && chown -R $USERNAME /commandhistory \
     && echo "$SNIPPET" >> "/home/$USERNAME/.bashrc" \
-    && sed -i '^/__bash_prompt$/d' "/home/$USERNAME/.bashrc"
+    && sed -i '/^__bash_prompt$/d' "/home/$USERNAME/.bashrc"
 # ^ fix weird issues with shell not handling line wrapping
 
 # buildroot dependencies