fixed submodule added with ssh - while all others with https

[rasmus-madsen]

When the software2026 was added as a submodule is was done with ssh, this differs from all other submodules, which are added with https.
and adds a requirement to the user to add a key for Github.

I think we should keep the submodules the same style.
also it is not really convinient to have to add a key to every machine one wants to add chipyard to

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