Fix small typo in M2M100 doc
Author: SaulLu
Pull request: yes

# What does this PR do?

Reading the M2M100 documentation, I think a little typo has crept into the code snippet.
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## Before submitting
- [x] This PR fixes a typo or improves the docs (you can dismiss the other checks if that's the case).
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## Who can review?

Anyone in the community is free to review the PR once the tests have passed and @patil-suraj :slightly_smiling_face: 
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