patch 9.0.1234: the code style has to be checked manually

Problem:    The code style has to be checked manually.
Solution:   Add basic code style checks in a test.  Fix or avoid uncovered
            problems.
diff --git a/src/if_lua.c b/src/if_lua.c
index 6941789..45f233f 100644
--- a/src/if_lua.c
+++ b/src/if_lua.c
@@ -657,9 +657,11 @@
 
 	    lua_pushvalue(L, pos);
 	    lua_tableref = luaL_ref(L, LUA_REGISTRYINDEX);
-	    if (lua_getmetatable(L, pos)) {
+	    if (lua_getmetatable(L, pos))
+	    {
 		lua_getfield(L, -1, LUA___CALL);
-		if (lua_isfunction(L, -1)) {
+		if (lua_isfunction(L, -1))
+		{
 		    char_u *name;
 		    int lua_funcref = luaL_ref(L, LUA_REGISTRYINDEX);
 		    luaV_CFuncState *state = ALLOC_CLEAR_ONE(luaV_CFuncState);
@@ -827,7 +829,8 @@
 	luatyp *o = NULL; \
 	if (obj == NULL) \
 	    lua_pushnil(L); \
-	else { \
+	else \
+	{ \
 	    luaV_getudata(L, obj); \
 	    if (lua_isnil(L, -1)) /* not interned? */ \
 	    { \