docs, scripts: Fix inheritance explanation and help text typo

[vipocenka]

docs/contracts/inheritance.rst:

• The text incorrectly stated that a super call in a contract defined as Final is Base1, Base2 would invoke the function in Base1.
• According to Solidity's C3 linearization rules (right-to-left), the next contract in the inheritance graph is Base2. The change corrects the text to state that Base2.emitEvent() is called, resolving a logical contradiction in the documentation.

scripts/externalTests/benchmark_diff.py:

• The verb replace was changed to replaces to agree with its singular subject, improving the clarity of the script's usage instructions.

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