fix: reading position of a request body

[snaka]

Fixes #441

Fix reading position of a request body which middleware passed to an application.

Checklist

• [x] I acknowledge that all my contributions will be made under the project's license
• [x] I have made a material change to the repo (functionality, testing, spelling, grammar)
• [x] I have read the Contribution Guidelines and my PR follows them
• [x] I have titled the PR appropriately
• [x] I have updated my branch with the main branch
• [x] I have added tests that prove my fix is effective or that my feature works
• [x] I have added necessary documentation about the functionality in the appropriate .md file It has not changed any functionalities.
• [x] have added inline documentation to the code I modified Modified codes are absolutely obvious

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