fix: Lock task to v3.39.2 to work around behaviour change in v3.40.0.

.devcontainer/Dockerfile

@@ -10,8 +10,10 @@ RUN ./tools/scripts/lib_install/linux/install-dev.sh
 RUN ./tools/scripts/lib_install/linux/install-lib.sh
 
 # NOTE:
-# `task` doesn't have an apt/yum package so we use its install script.
-RUN sh -c "$(curl --location https://taskfile.dev/install.sh)" -- -d -b /usr/local/bin
+# - `task` doesn't have an apt/yum package so we use its install script.
+# - We lock task's version since v3.40.0 and higher change the behaviour of how undefined variables
+#   are treated in `ref` statements, causing yscope-dev-utils' `validate-checksum` task to fail.
+RUN sh -c "$(curl --location https://taskfile.dev/install.sh)" -- -d -b /usr/local/bin v3.39.2
 
 # Remove cached files
 RUN apt-get clean \

.github/workflows/code-linting-checks.yaml

@@ -31,8 +31,11 @@ jobs:
         with:
           python-version: "3.10"
 
+      # We lock task's version since v3.40.0 and higher change the behaviour of how undefined
+      # variables are treated in `ref` statements, causing yscope-dev-utils' `validate-checksum`
+      # task to fail.
       - name: "Install task"
-        run: "npm install -g @go-task/cli"
+        run: "npm install -g @go-task/cli@3.39.2"
 
       - if: "matrix.os == 'macos-latest'"
         name: "Install coreutils (for md5sum)"

README.md

@@ -3,7 +3,7 @@ Follow the steps below to develop and contribute to the project.
 
 ## Requirements
 * Python 3.10 or higher
-* [Task] 3.38.0 or higher
+* [Task] >= 3.38.0, < 3.40.0
 
 ## Set up
 Initialize and update submodules: