rename env PLUGIN_URL

[milahu]

the env name should be more absolute than PLUGIN_URL

webview_deno/src/ffi.ts

Lines 4 to 7 in 9c3bff6

	const version = "0.7.3";
	const cache = Deno.env.get("PLUGIN_URL") === undefined ? "use" : "reloadAll";
	const url = Deno.env.get("PLUGIN_URL") ??
	`https://github.com/webview/webview_deno/releases/download/${version}/`;

this env holds the folder of libwebview.so so rename to ...

WEBVIEW_DENO_LIBWEBVIEW?
WEBVIEW_DENO_LIB?
DENO_LIBWEBVIEW?
DENO_WEBVIEW_LIB?

also its not an (optional) "plugin" but an essential dependency

fix merged in https://github.com/milahu/webview_deno