Update README.mdx (#26)

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exercises/05.generated/02.problem.dynamic/README.mdx

@@ -2,7 +2,7 @@
 
 <EpicVideo url="https://www.epicweb.dev/workshops/data-modeling-deep-dive/generating-seed-data/dynamically-generating-data" />
 
-🧝‍♂️ I've fixed things up a little bit and add some organization for us. Just so
+🧝‍♂️ I've fixed things up a little bit and added some organization for us. Just so
 you know. I've also created a couple utility functions for creating users to
 make that data a tad bit more realistic and creating images that we've already
 got in our `tests/fixtures/images` directory.