verification: fix unnecessary lazy evaluations findings

Clippy is flagging a couple instances of this:
```
error: unnecessary closure used with `bool::then`
   --> src/verification/android.rs:251:18
    |
251 |         .map(|o| (!o.is_null()).then(|| o))
    |                  ^^^^^^^^^^^^^^^----------
    |                                 |
    |                                 help: use `then_some(..)` instead: `then_some(o)`
    |
```

This commit applies the recommended fix.

src/verification/android.rs

@@ -248,7 +248,7 @@ fn extract_result_info(env: &JNIEnv<'_>, result: JObject<'_>) -> (VerifierStatus
     let msg = env
         .get_field(result, "message", "Ljava/lang/String;")
         .and_then(|m| m.l())
-        .map(|o| (!o.is_null()).then(|| o))
+        .map(|o| (!o.is_null()).then_some(o))
         .and_then(|s| s.map(|s| JavaStr::from_env(env, s.into())).transpose())
         .unwrap();
 

src/verification/windows.rs

@@ -184,7 +184,7 @@ impl Certificate {
                 CERT_SET_PROPERTY_IGNORE_PERSIST_ERROR_FLAG,
                 prop_data,
             ) == TRUE)
-                .then(|| ())
+                .then_some(())
         })
     }
 }