CH03::Bitcoin Core wallet warning: drop

Bitcoin Core works fine as a wallet (and I personally use it).  Although
it doesn't implement BIP39, it does implement BIP32 and many other
standards, including some significant improvements over other wallets
(such as descriptors and HWI support ).  It's also the easiest way to
take advantage of the additional verification and privacy advantages of
running a full node.

ch03.asciidoc

@@ -26,18 +26,6 @@ implemented. Bitcoin Core implements all aspects of bitcoin, including
 wallets, a transaction and block validation engine, and all modern parts
 of Bitcoin peer-to-peer communication.
 
-[WARNING]
-====
-((("wallets", "best practices for")))((("bitcoin improvement proposals",
-"Mnemonic Code Words (BIP-39)")))((("bitcoin improvement proposals",
-"Hierarchical Deterministic Wallets (BIP-32/BIP-44)")))Even though
-Bitcoin Core includes a reference implementation of a wallet, this is
-not intended to be used as a production wallet for users or for
-applications. Application developers are advised to build wallets using
-modern standards such as BIP-39 and BIP-32 (see <<mnemonic_code_words>>
-and <<hd_wallets>>). BIP stands for _Bitcoin Improvement Proposal_.
-====
-
 <<bitcoin_core_architecture>> shows the architecture of Bitcoin
 Core.((("Bitcoin Core", "architecture")))