fix(devcontainer): copy all source

since it is not available in base image anymore

.devcontainer/Dockerfile

@@ -6,9 +6,9 @@ USER root
 RUN curl -sL https://aka.ms/InstallAzureCLIDeb | bash
 USER $USER
 
+COPY . .
 # install devcontainer requirements
 RUN pip install -e .[dev,test]
 
 # docs requirements are in a separate file for the GitHub Action
-COPY docs/requirements.txt docs/requirements.txt
 RUN pip install -r docs/requirements.txt