Replace gif with one that has lower fps

[liamhuber]

Performance sucked and made it look laggy. New one has half as many frames. This seems to render in browser better.

[github-actions[bot]]

:point_left: Launch a binder notebook on branch _pyiron/ironflow/downscalegif

[github-actions[bot]]

Pull Request Test Coverage Report for Build 4953158815

• 0 of 0 changed or added relevant lines in 0 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 61.507%

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Totals
Change from base Build 4953052180:	0.0%
Covered Lines:	2221
Relevant Lines:	3611

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💛 - Coveralls