fix param import transition

* fix param import transition for MC_DTERM_CUTOFF

The previous implementation did not work, as there was a check for
param_find_no_notification() returning PARAM_INVALID for IMU_DGYRO_CUTOFF,
and therefore would not call param_modify_on_import().

This moves param_modify_on_import() before the check and makes it modify
the bson node directly.

* parameters: fix param import transition when testing is enabled

BUILD_TESTING is used for unit test builds, PX4_TESTING is used to enable additional test material within PX4

Co-authored-by: Daniel Agar <daniel@agar.ca>

src/lib/parameters/flashparams/flashparams.cpp

@@ -229,6 +229,8 @@ param_import_callback(bson_decoder_t decoder, void *priv, bson_node_t node)
 		return 0;
 	}
 
+	param_modify_on_import(node);
+
 	/*
 	 * Find the parameter this node represents.  If we don't know it,
 	 * ignore the node.
@@ -301,8 +303,6 @@ param_import_callback(bson_decoder_t decoder, void *priv, bson_node_t node)
 		goto out;
 	}
 
-	param_modify_on_import(node->name, node->type, v);
-
 	if (param_set_external(param, v, state->mark_saved, true)) {
 
 		debug("error setting value for '%s'", node->name);