BUILD-7247 Use fixed poetry version according to the doc:

Sebastien Vermeille · Sebastien Vermeille · commit 1328b4f3dcf5 · 2025-01-14T09:43:16.000+01:00
https://python-poetry.org/docs/#installing-with-the-official-installer
diff --git a/.cirrus/poetry.Dockerfile b/.cirrus/poetry.Dockerfile
@@ -19,6 +19,6 @@ RUN cd /usr/local/bin \
 
 USER sonarsource
 
-RUN curl -sSL https://install.python-poetry.org | python3 -
+RUN curl -sSL https://install.python-poetry.org | python3 - --version 1.8.4
 ENV PATH="/home/sonarsource/bin:${PATH}"
 ENV PATH="${PATH}:/home/sonarsource/.local/bin"
