Create spinner-lockup.md

Author: TheSonOfThomp

.changeset/spinner-lockup.md

@@ -0,0 +1,14 @@
+---
+'@leafygreen-ui/loading-indicator': minor
+---
+
+Adds `SpinnerLockup` component to correctly align a Spinner and description text
+
+```tsx
+<SpinnerLockup direction="horizontal">
+  <SpinnerLockup.Spinner
+    size={'default'}
+  />
+  <SpinnerLockup.Description>Loading...</SpinnerLockup.Description>
+</SpinnerLockup>
+```