do not rely on regex

This test will verify that the usage of `segment` is correct. Before we
were relying on a regex and check for `(=.*)` which would also match
_inside_ of the quoted value.

Author: RobinMalfait

packages/tailwindcss/src/variants.test.ts

@@ -2076,6 +2076,7 @@ test('data', async () => {
       'data-[potato=salad]:flex',
       'data-[potato_=_"salad"]:flex',
       'data-[potato_^=_"salad"]:flex',
+      'data-[potato="^_="]:flex',
       'data-[foo=1]:flex',
       'data-[foo=bar_baz]:flex',
       "data-[foo$='bar'_i]:flex",
@@ -2170,6 +2171,10 @@ test('data', async () => {
       display: flex;
     }
 
+    .data-\\[potato\\=\\"\\^_\\=\\"\\]\\:flex[data-potato="^ ="] {
+      display: flex;
+    }
+
     .data-\\[foo\\=1\\]\\:flex[data-foo="1"] {
       display: flex;
     }