GHActions:Linux: Upgrade to GCC 10

.github/workflows/scripts/linux/generate-cmake.sh

@@ -3,8 +3,8 @@
 set -e
 
 if [ "${COMPILER}" = "gcc" ]; then
-  export CC=gcc-8
-  export CXX=g++-8
+  export CC=gcc-10
+  export CXX=g++-10
 else
   export CC=clang
   export CXX=clang++

.github/workflows/scripts/linux/install-packages.sh

@@ -36,10 +36,10 @@ declare -a PCSX2_PACKAGES=(
 )
 
 if [ "${COMPILER}" = "gcc" ]; then
-  BUILD_PACKAGES+=("g++-8-multilib")
+  BUILD_PACKAGES+=("g++-10-multilib")
 else
   BUILD_PACKAGES+=("clang")
-  PCSX2_PACKAGES+=("libstdc++-8-dev")
+  PCSX2_PACKAGES+=("libstdc++-10-dev")
 fi
 
 # - https://github.com/actions/virtual-environments/blob/main/images/linux/Ubuntu2004-README.md