Make `regen:projectDeveloper` optional in C01 project SHACL

[blushi]

Description

Per latest design: https://www.figma.com/file/TyhFaXqko9F8OvLEE4Zomg/Issuer-Create%2FEdit-Projects%2C-Credit-Class%2C-Batches?node-id=2%3A4501

Ref: https://github.com/regen-network/regen-registry/issues/905

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