tests: remove WESTON_BUILD_DIR from env

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Signed-off-by: Pekka Paalanen <pekka.paalanen@collabora.co.uk>
Reviewed-by: Daniel Stone <daniels@collabora.com>
Reviewed-by: Emre Ucan <eucan@de.adit-jv.com>

tests/weston-tests-env

@@ -55,7 +55,6 @@ case $TEST_FILE in
 		set -x
 		WESTON_MODULE_MAP="${WESTON_MODULE_MAP}" \
 		WESTON_DATA_DIR=$abs_top_srcdir/data \
-		WESTON_BUILD_DIR=$abs_builddir \
 		WESTON_TEST_REFERENCE_PATH=$abs_top_srcdir/tests/reference \
 		$WESTON --backend=$MODDIR/$BACKEND \
 			--no-config \
@@ -69,7 +68,6 @@ case $TEST_FILE in
 		set -x
 		WESTON_MODULE_MAP="${WESTON_MODULE_MAP}" \
 		WESTON_DATA_DIR=$abs_top_srcdir/data \
-		WESTON_BUILD_DIR=$abs_builddir \
 		WESTON_TEST_REFERENCE_PATH=$abs_top_srcdir/tests/reference \
 		$WESTON --backend=$MODDIR/$BACKEND \
 			${CONFIG} \
@@ -86,7 +84,6 @@ case $TEST_FILE in
 		set -x
 		WESTON_MODULE_MAP="${WESTON_MODULE_MAP}" \
 		WESTON_DATA_DIR=$abs_top_srcdir/data \
-		WESTON_BUILD_DIR=$abs_builddir \
 		WESTON_TEST_REFERENCE_PATH=$abs_top_srcdir/tests/reference \
 		WESTON_TEST_CLIENT_PATH=$abs_builddir/$TEST_FILE \
 		$WESTON --backend=$MODDIR/$BACKEND \
@@ -102,7 +99,6 @@ case $TEST_FILE in
 		set -x
 		WESTON_MODULE_MAP="${WESTON_MODULE_MAP}" \
 		WESTON_DATA_DIR=$abs_top_srcdir/data \
-		WESTON_BUILD_DIR=$abs_builddir \
 		WESTON_TEST_REFERENCE_PATH=$abs_top_srcdir/tests/reference \
 		WESTON_TEST_CLIENT_PATH=$abs_builddir/$TEST_FILE \
 		$WESTON --backend=$MODDIR/$BACKEND \