auto, wasm-wc: Copy the .so into build/lib/unit/modules/

Normally when the language modules are built, they are built directly
into the build/lib/unit/modules/ directory.

This then allows Unit to find them without being installed. This is
useful for things like the pytests.

This wasn't happening for the wasm-wasi-component language module. So we
now copy it over and give it the right name as part of the make/build
process.

Reported-by: Andrei Zeliankou <zelenkov@nginx.com>
Fixes: 4e6d7e876 ("Wasm-wc: Wire it up to the build system")
Signed-off-by: Andrew Clayton <a.clayton@nginx.com>

auto/modules/wasm-wasi-component

@@ -110,6 +110,8 @@ ${NXT_WCM_MODULE}:	${NXT_WCM_MOD_CARGO}
 
 ${NXT_WCM_MOD_CARGO}: ${NXT_WCM_DEPS}
 	$NXT_CARGO_CMD
+	@install -p $NXT_WCM_MOD_CARGO \\
+		build/lib/unit/modules/${NXT_WCM_MOD_NAME}
 
 install: ${NXT_WCM_MODULE}-install