Update CHANGELOG.md, fix typos

[BobConanDev]

I really enjoyed using this project, nice work! Found a couple of typos in the CHANGELOG.md though 😛

Please take note of our contributing guidelines: https://docs.laravel-excel.com/3.1/getting-started/contributing.html
Filling out the template is required. Any pull request that does not include enough information to be reviewed in a timely manner may be closed at the maintainers' discretion.

1️⃣ Why should it be added? What are the benefits of this change?
clear reading
2️⃣ Does it contain multiple, unrelated changes? Please separate the PRs out.
No
3️⃣ Does it include tests, if possible?
No
4️⃣ Any drawbacks? Possible breaking changes?
No
5️⃣ Mark the following tasks as done:

• Checked the codebase to ensure that your feature doesn't already exist.
• Take note of the contributing guidelines.
• Checked the pull requests to ensure that another person hasn't already submitted a fix.
• Added tests to ensure against regression.

6️⃣ Thanks for contributing! 🙌