Clarify HasMap initial capacity and load factor instructions

[Alfa06N]

Because

To clarify the instructions for creating a HashMap, specifying the initial capacity should be set to 16 to match the test setup.

This PR

• Added clarification to the instructions by stating the initial capacity for HashMap should be 16.
• Updated test instructions to reflect the requirement of 16 initial buckets for clarity.

Issue

Related to #29162

Additional Information

This update was made to improve clarity, and the change aligns the curriculum instructions with the existing test setup

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