chore(devcontainer): update base image to ubnutu 24.04

Author: urish

.devcontainer/Dockerfile

@@ -1,4 +1,4 @@
-ARG VARIANT=ubuntu-22.04
+ARG VARIANT=ubuntu-24.04
 FROM mcr.microsoft.com/vscode/devcontainers/base:${VARIANT}
 
 ENV DEBIAN_FRONTEND=noninteractive
@@ -15,7 +15,8 @@ RUN git clone https://github.com/TinyTapeout/tt-support-tools /ttsetup/tt-suppor
 COPY test/requirements.txt /ttsetup/test_requirements.txt
 COPY .devcontainer/copy_tt_support_tools.sh /ttsetup
 
-RUN pip3 install -r /ttsetup/test_requirements.txt -r /ttsetup/tt-support-tools/requirements.txt
+RUN python -m venv /ttsetup/venv
+RUN /ttsetup/venv/bin/pip install -r /ttsetup/test_requirements.txt -r /ttsetup/tt-support-tools/requirements.txt
 
 # Install verible (for formatting)
 RUN umask 022 && \
@@ -24,4 +25,4 @@ RUN umask 022 && \
     chmod 755 /usr/local/bin
 
 # Install LibreLane
-RUN pip3 install librelane==2.4.2
+RUN /ttsetup/venv/bin/pip install librelane==2.4.2

.devcontainer/devcontainer.json

@@ -25,5 +25,6 @@
       "dockerDashComposeVersion": "none"
     }
   },
+  "postCreateCommand": "echo 'source /ttsetup/venv/bin/activate' >> ~/.bashrc",
   "postStartCommand": "/ttsetup/copy_tt_support_tools.sh"
 }