Revert "Revert GCC 12 downgrade for Linux builds"

This reverts commit a3c4349.

See details in duckdb/duckdb#17963.

Author: staticlibs

.github/workflows/Java.yml

@@ -49,7 +49,9 @@ jobs:
             cat /etc/os-release
             dnf install -y \
               java-1.8.0-openjdk-devel \
-              ninja-build
+              ninja-build \
+              gcc-toolset-12-gcc-c++
+            source /opt/rh/gcc-toolset-12/enable
             make -C /duckdb release
           "
 
@@ -152,7 +154,9 @@ jobs:
             cat /etc/os-release
             dnf install -y \
               java-1.8.0-openjdk-devel \
-              ninja-build
+              ninja-build \
+              gcc-toolset-12-gcc-c++
+            source /opt/rh/gcc-toolset-12/enable
             make -C /duckdb release
           "