Fix typos in Documentation and Code Comments

[vipocenka]

This pull request addresses several grammatical and typographical issues across multiple files. Specifically:

1. Replaced incorrect article usage (a -> an) in comments and documentation to improve clarity and adherence to grammatical rules.
2. Corrected phrasing to enhance readability.

Changes include:

• utils.go: Fixed article usage for "upstream binding data structure."
• toeplitz.go and toeplitz_test.go: Corrected the phrase "a also concise representation" to "also a concise representation."
• config.go: Updated "a operator's public IP" to "an operator's public IP."

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Checks

• I've made sure the tests are passing.
• I've checked the new test coverage and the coverage percentage didn't drop.
• Testing Strategy:
  • Unit tests
  • Integration tests
  • This PR is not tested.