No it is not possible to use a gMSA as a user to run processes on Unix/Linux.
The gMSA is created with an objectCategory of ms-DS-Group-Managed-Service-Account:
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objectCategory: CN=ms-DS-Group-Managed-Service-Account,CN=Schema,CN=Configuration,DC=mydomain,DC=com
objectClass: user
objectClass: computer
objectClass: msDS-GroupManagedServiceAccount
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Therefore the client is unable to cache this account.