More more fixes

Author: vstinner

.github/workflows/build.yml

@@ -282,7 +282,7 @@ jobs:
         - bolt: true
           free-threading: true
         # BOLT currently crashes during instrumentation on aarch64
-        - os: ubuntu-26.04-arm
+        - os: ubuntu-24.04-arm
           bolt: true
     uses: ./.github/workflows/reusable-ubuntu.yml
     with:

.github/workflows/posix-deps-apt.sh

@@ -13,7 +13,6 @@ apt-get -yq --no-install-recommends install \
     libgdbm-compat-dev \
     libgdbm-dev \
     liblzma-dev \
-    libmpdec-dev \
     libncurses5-dev \
     libreadline6-dev \
     libsqlite3-dev \