[ENH] Added ROCKAD anomaly detector to aeon

[pattplatt]

What does this implement/fix? Explain your changes.

Implemented the ROCKAD anomaly detector.

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I have added the following labels to this PR based on the title: [ $\color{#FEF1BE}{\textsf{enhancement}}$ ]. I have added the following labels to this PR based on the changes made: [ $\color{#6F6E8D}{\textsf{anomaly detection}}$ ]. Feel free to change these if they do not properly represent the PR.

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