Remove corpus seeds and fix typo in docs

Author: oetr

docs/fuzz-targets.md

@@ -194,7 +194,7 @@ Alternatively, you can add a new script to your package.json:
 
 Files matched by the flags `--include` or `--custom_hooks`, and not matched by
 the flag `--exclude` will be included in the coverage report. It is recommended
-to disable coverage report generation during fuzzing, because of a substantial
+to disable coverage report generation during fuzzing, because of the substantial
 overhead that it adds.
 
 ### Coverage report directory

docs/jest-integration.md

@@ -28,7 +28,7 @@ your project. To do so, execute the following command in your project root
 directory.
 
 ```shell
-npm install --save-dev @jazzer.js/jest-integration
+npm install --save-dev @jazzer.js/jest-runner
 ```
 
 This will install the custom Jest runner along with all other required Jazzer.js