Do not mix tabs and spaces in GitHub CI script.

.github/workflows/cibuild.sh

@@ -12,27 +12,27 @@ CXX="g++${COMPILER_VERSION:+-$COMPILER_VERSION}"
 set -ex
 
 for phase in "${PHASES[@]}"; do
-    case $phase in
-    CONFIGURE)
-        opts=(
-            --enable-libargon2
-        )
+	case $phase in
+	CONFIGURE)
+		opts=(
+			--enable-libargon2
+		)
 
-        sudo -E git clean -xdf
+		sudo -E git clean -xdf
 
-        ./autogen.sh
-        CC="$CC" CXX="$CXX" CFLAGS="${CFLAGS[@]}" CXXFLAGS="${CXXFLAGS[@]}" ./configure "${opts[@]}"
-        ;;
-    MAKE)
-        make -j
-        make -j -C tests check-programs
-        ;;
-    CHECK)
-        make check
-        ;;
+		./autogen.sh
+		CC="$CC" CXX="$CXX" CFLAGS="${CFLAGS[@]}" CXXFLAGS="${CXXFLAGS[@]}" ./configure "${opts[@]}"
+		;;
+	MAKE)
+		make -j
+		make -j -C tests check-programs
+		;;
+	CHECK)
+		make check
+		;;
 
-    *)
-        echo >&2 "Unknown phase '$phase'"
-        exit 1
-    esac
+	*)
+		echo >&2 "Unknown phase '$phase'"
+		exit 1
+	esac
 done