Missing implementation of pretty_repr method in ImagePromptTemplate class.

[FedericoOmoto]

Checked

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Feature request

Implement the pretty_repr method in the ImagePromptTemplate class.
Right now it raises a NotImplementedError exception.

Motivation

All other PromptTemplateclasses fully implement the pretty_repr method, it's annoying not having it correctly implemented in the ImagePromptTemplate class.

Proposal (If applicable)

No response