Fix typo in prompts-guide (#1131)

Fix typo in prompts-guide

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Author: gabtorre

docs/cody/prompts-guide.mdx

@@ -270,7 +270,7 @@ This prompt can help you if you want to generate unit tests for your code based
 
 >You're working with Golang and need Cody to generate unit tests that comply with your team’s conventions. Your organization follows a specific structure for tests, including table-driven tests and `require` from the `testify` package for assertions. However, Cody might provide a simple test that does not align with your standards.
 
-While you can use the default `generate-unit-tests` prompt but to get the desired output, you can customize e the prompt to include the following:
+While you can use the default `generate-unit-tests` prompt but to get the desired output, you can customize the prompt to include the following:
 
 ```
 Please generate Golang unit tests that adhere to the following conventions: