Github Actions typo fix. [ci skip]

.github/workflows/ci-scripts/docker.sh

@@ -1,5 +1,16 @@
 #!/bin/bash
 
+echo "Using docker:"
+echo "BRANCH: $BRANCH"
+echo "IMAGE: $IMAGE"
+echo "NLS: $NLS"
+echo "TOOL: $TOOL"
+echo "CC: $CC"
+echo "CXX: $CXX"
+echo "CXXSTD: $CXXSTD"
+echo "CFG: $CFG"
+echo "LTO: $LTO"
+
 scons wesnoth wesnothd campaignd boost_unit_tests build="$CFG" \
     ctool="$CC" cxxtool="$CXX" cxx_std="$CXX_STD" \
     extra_flags_config="-pipe" strict=true forum_user_handler=true \

.github/workflows/ci-scripts/ubuntu.sh

@@ -32,5 +32,5 @@ docker build -t wesnoth-repo:"$IMAGE"-"$BRANCH" -f utils/dockerbuilds/travis/Doc
 docker run --cap-add=ALL --privileged \
     --volume ~/build-cache:/home/wesnoth-travis/build \
     --env BRANCH --env IMAGE --env NLS --env TOOL --env CC --env CXX \
-    --env CFG --env LTO \
+    --env CXX_STD --env CFG --env LTO \
     wesnoth-repo:"$IMAGE"-"$BRANCH" ./.github/workflows/ci-scripts/docker.sh