Add grow and shrink aliases (#5733)

This adds `grow-*` and `shrink-*` utilities as aliases for `flex-grow-*` and `flex-shrink-*` since those names are unnecessarily verbose. We will stop documenting the long form ones and consider them deprecated.

```diff
- <div class="flex-grow-0 flex-shrink">
+ <div class="grow-0 shrink">
```

src/corePlugins.js

@@ -645,8 +645,14 @@ export let corePlugins = {
   maxWidth: createUtilityPlugin('maxWidth', [['max-w', ['maxWidth']]]),
 
   flex: createUtilityPlugin('flex'),
-  flexShrink: createUtilityPlugin('flexShrink', [['flex-shrink', ['flex-shrink']]]),
-  flexGrow: createUtilityPlugin('flexGrow', [['flex-grow', ['flex-grow']]]),
+  flexShrink: createUtilityPlugin('flexShrink', [
+    ['flex-shrink', ['flex-shrink']], // Deprecated
+    ['shrink', ['flex-shrink']],
+  ]),
+  flexGrow: createUtilityPlugin('flexGrow', [
+    ['flex-grow', ['flex-grow']], // Deprecated
+    ['grow', ['flex-grow']],
+  ]),
   flexBasis: createUtilityPlugin('flexBasis', [['basis', ['flex-basis']]]),
 
   tableLayout: ({ addUtilities }) => {