build(deps): Bump github.com/decred/dcrd/dcrec/secp256k1/v4 from 4.1.0 to 4.2.0 (#15839)

Bumps [github.com/decred/dcrd/dcrec/secp256k1/v4](https://github.com/decred/dcrd) from 4.1.0 to 4.2.0.
<details>
<summary>Commits</summary>
<ul>
<li><a href="https://github.com/decred/dcrd/commit/bacf8444a8bc79178f9eb2c65477ab6df01a6439"><code>bacf844</code></a> secp256k1: Prepare v4.2.0.</li>
<li><a href="https://github.com/decred/dcrd/commit/e0ad9b868795343559f0436a1ef6fa6bdf5000aa"><code>e0ad9b8</code></a> secp256k1: Update PrivKeyFromBytes comment.</li>
<li><a href="https://github.com/decred/dcrd/commit/6c5b953d28abb57bcf52b1088eb2b22ce0b522bb"><code>6c5b953</code></a> secp256k1: Add GeneratePrivateKeyFromRand tests.</li>
<li><a href="https://github.com/decred/dcrd/commit/bd0b82d0be0fca0f91dbc22628de11f7915a234b"><code>bd0b82d</code></a> secp256k1: Require concerete rand for privkey gen.</li>
<li><a href="https://github.com/decred/dcrd/commit/b4fab9efd838469f718fc943f2f19828d7829b49"><code>b4fab9e</code></a> chaincfg/chainhash: Prepare v1.0.4.</li>
<li><a href="https://github.com/decred/dcrd/commit/d71616bddb615ef368382dcc7cb6cf2d78d858c1"><code>d71616b</code></a> secp256k1: Add GeneratePrivateKeyFromRand function</li>
<li><a href="https://github.com/decred/dcrd/commit/9aa79ec168f6145484b62c88701fec9634a539f4"><code>9aa79ec</code></a> chaincfg: Introduce subsidy split change r2 agenda.</li>
<li><a href="https://github.com/decred/dcrd/commit/7db7325c42353d7ab43deb69e2107b434488691c"><code>7db7325</code></a> chaincfg: Introduce BLAKE3 PoW agenda.</li>
<li><a href="https://github.com/decred/dcrd/commit/ce46220cf7722142aa91ec52507160f9ca63880d"><code>ce46220</code></a> secp256k1: Fix typo in a doc comment</li>
<li><a href="https://github.com/decred/dcrd/commit/ca02bcaf5a5dde671dae59eed26887f30ada7d51"><code>ca02bca</code></a> docs: Add release notes for v1.7.7.</li>
<li>Additional commits viewable in <a href="https://github.com/decred/dcrd/compare/blockchain/v4.1.0...dcrec/secp256k1/v4.2.0">compare view</a></li>
</ul>
</details>
<br />


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</details>

client/v2/go.mod

@@ -46,7 +46,7 @@ require (
 	github.com/cosmos/ledger-cosmos-go v0.13.0 // indirect
 	github.com/danieljoos/wincred v1.1.2 // indirect
 	github.com/davecgh/go-spew v1.1.1 // indirect
-	github.com/decred/dcrd/dcrec/secp256k1/v4 v4.1.0 // indirect
+	github.com/decred/dcrd/dcrec/secp256k1/v4 v4.2.0 // indirect
 	github.com/dvsekhvalnov/jose2go v1.5.0 // indirect
 	github.com/fsnotify/fsnotify v1.6.0 // indirect
 	github.com/getsentry/sentry-go v0.19.0 // indirect

client/v2/go.sum

@@ -160,9 +160,9 @@ github.com/danieljoos/wincred v1.1.2/go.mod h1:GijpziifJoIBfYh+S7BbkdUTU4LfM+QnG
 github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
-github.com/decred/dcrd/crypto/blake256 v1.0.0 h1:/8DMNYp9SGi5f0w7uCm6d6M4OU2rGFK09Y2A4Xv7EE0=
-github.com/decred/dcrd/dcrec/secp256k1/v4 v4.1.0 h1:HbphB4TFFXpv7MNrT52FGrrgVXF1owhMVTHFZIlnvd4=
-github.com/decred/dcrd/dcrec/secp256k1/v4 v4.1.0/go.mod h1:DZGJHZMqrU4JJqFAWUS2UO1+lbSKsdiOoYi9Zzey7Fc=
+github.com/decred/dcrd/crypto/blake256 v1.0.1 h1:7PltbUIQB7u/FfZ39+DGa/ShuMyJ5ilcvdfma9wOH6Y=
+github.com/decred/dcrd/dcrec/secp256k1/v4 v4.2.0 h1:8UrgZ3GkP4i/CLijOJx79Yu+etlyjdBU4sfcs2WYQMs=
+github.com/decred/dcrd/dcrec/secp256k1/v4 v4.2.0/go.mod h1:v57UDF4pDQJcEfFUCRop3lJL149eHGSe9Jvczhzjo/0=
 github.com/desertbit/timer v0.0.0-20180107155436-c41aec40b27f h1:U5y3Y5UE0w7amNe7Z5G/twsBW0KEalRQXZzf8ufSh9I=
 github.com/dgraph-io/badger v1.6.0 h1:DshxFxZWXUcO0xX476VJC07Xsr6ZCBVRHKZ93Oh7Evo=
 github.com/dgraph-io/badger v1.6.0/go.mod h1:zwt7syl517jmP8s94KqSxTlM6IMsdhYy6psNgSztDR4=