New Entry CalculateAverage_muratlevent.java

[muratlevent]

Check List:

• You have run ./mvnw verify and the project builds successfully
• Tests pass (./test.sh <username> shows no differences between expected and actual outputs)
• All formatting changes by the build are committed
• Your launch script is named calculate_average_<username>.sh (make sure to match casing of your GH user name) and is executable
• Output matches that of calculate_average_baseline.sh
• For new entries, or after substantial changes: When implementing custom hash structures, please point to where you deal with hash collisions (line number)

• Execution time: 56.54 secs
• Execution time of reference implementation: 220.63 secs
• Specs of my system : M1 PRO 14" with 8 core CPU and 16 GB RAM

I am aware that the One Billion Row Challenge has officially concluded, but I wanted to take this opportunity to further explore and test my skills.