NEW YORK—Robinhood Markets Inc. said on Wednesday it plans to begin testing cryptocurrency wallets next month, with a broader rollout in early 2022, allowing its users to move supported digital currencies in and out of their brokerage accounts. The Menlo Park-based retail brokerage currently allows buying, selling, and holding of certain cryptocurrencies, like bitcoin and dogecoin, and last quarter saw crypto transactions exceed equities transactions for the first time. Customers of Robinhood, which benefited from a boom in retail trading during the pandemic, have long asked for crypto wallets, which would allow them to participate more broadly in blockchain-based ecosystems, such as buying virtual assets like non-fungible tokens (NTFs) on the Ethereum network. “This is the natural next step for us when we think about democratizing finance for all, being able to have a lot more people from a lot of different contexts participate in this emerging market, and wallets …