fix: use absolute specifier for dynamic import

lib/normalised-import.js

@@ -1,8 +1,14 @@
+const path = require('path');
+
 // Normalise possible mjs/cjs/js file import.
-module.exports = async function(path) {
+module.exports = async function(modulePath) {
+  // Use Absolute specifiers
+  // https://nodejs.org/dist/latest-v16.x/docs/api/esm.html#import-specifiers
+  const p = 'file://' + path.resolve(modulePath);
+
   // 1. try path.mjs first
   try {
-    return await import(path + '.mjs');
+    return await import(p + '.mjs');
   } catch (e) {
     // ignore
     // console.error(e);
@@ -13,7 +19,7 @@ module.exports = async function(path) {
     // Note we use import() to load commonjs code,
     // it automatically provides module.exports in
     // default export.
-    return await import(path + '.cjs');
+    return await import(p + '.cjs');
   } catch (e) {
     // ignore
     // console.error(e);
@@ -25,7 +31,7 @@ module.exports = async function(path) {
     // Note we use import() to load commonjs code,
     // it automatically provides module.exports in
     // default export.
-    return await import(path + '.js');
+    return await import(p + '.js');
   } catch (e) {
     // ignore
     // console.error(e);