Add test for coverage

Author: Mrtenz

src/index.test.ts

@@ -4,6 +4,7 @@ import {
   SLIP10Node,
   secp256k1,
   ed25519,
+  isValidBIP32PathSegment,
 } from '.';
 
 // This is purely for coverage shenanigans
@@ -15,5 +16,6 @@ describe('index', () => {
     expect(SLIP10Node).toBeDefined();
     expect(secp256k1).toBeDefined();
     expect(ed25519).toBeDefined();
+    expect(isValidBIP32PathSegment).toBeDefined();
   });
 });