[react-strict-animated] Fix incorrect error message for invalid mass in SpringAnimation

The mass validation in the SpringAnimation constructor threw 'Damping value
must be greater than 0', a copy-paste of the preceding damping check. It now
reports 'Mass value must be greater than 0', matching the field being
validated (and the equivalent check in React Native's SpringAnimation).

Author: adityasingh2400

packages/react-strict-animated/src/web/__tests__/SpringAnimation-test.js

@@ -0,0 +1,30 @@
+/**
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ *
+ * @flow strict-local
+ */
+
+import SpringAnimation from '../animations/SpringAnimation';
+
+describe('SpringAnimation (web)', () => {
+  test('rejects a non-positive stiffness value', () => {
+    expect(
+      () => new SpringAnimation({ toValue: 1, stiffness: 0, damping: 10, mass: 1 })
+    ).toThrow('Stiffness value must be greater than 0');
+  });
+
+  test('rejects a non-positive damping value', () => {
+    expect(
+      () => new SpringAnimation({ toValue: 1, stiffness: 100, damping: 0, mass: 1 })
+    ).toThrow('Damping value must be greater than 0');
+  });
+
+  test('rejects a non-positive mass value', () => {
+    expect(
+      () => new SpringAnimation({ toValue: 1, stiffness: 100, damping: 10, mass: 0 })
+    ).toThrow('Mass value must be greater than 0');
+  });
+});

packages/react-strict-animated/src/web/animations/SpringAnimation.js

@@ -109,7 +109,7 @@ export default class SpringAnimation implements AnimatedAnimation {
       throw new Error('Damping value must be greater than 0');
     }
     if (this.#mass <= 0) {
-      throw new Error('Damping value must be greater than 0');
+      throw new Error('Mass value must be greater than 0');
     }
   }