fix: update eth-sig-util to fix a regression (#131)

A regression was introduced on eth-sig-util 6.0.1 and 7.0.0, see:
MetaMask/eth-sig-util#340

packages/snap/package.json

@@ -40,7 +40,7 @@
     "@ethereumjs/common": "^3.1.2",
     "@ethereumjs/tx": "^4.1.2",
     "@ethereumjs/util": "^8.0.5",
-    "@metamask/eth-sig-util": "^7.0.0",
+    "@metamask/eth-sig-util": "^7.0.1",
     "@metamask/keyring-api": "^1.0.0-rc.1",
     "@metamask/snaps-types": "^3.0.0",
     "@metamask/utils": "^8.1.0",

packages/snap/snap.manifest.json

@@ -7,7 +7,7 @@
     "url": "git+https://github.com/MetaMask/snap-simple-keyring.git"
   },
   "source": {
-    "shasum": "NAOMmdbgoD7cqPmVnR3ig9/ROEhZWpIIjmo9UjaKdG4=",
+    "shasum": "6LvLUNssp12iYOIQ/j5Ee3G+TKywMxFrWbe1v7/zdVk=",
     "location": {
       "npm": {
         "filePath": "dist/bundle.js",

yarn.lock

@@ -3164,18 +3164,17 @@ __metadata:
   languageName: node
   linkType: hard
 
-"@metamask/eth-sig-util@npm:^7.0.0":
-  version: 7.0.0
-  resolution: "@metamask/eth-sig-util@npm:7.0.0"
+"@metamask/eth-sig-util@npm:^7.0.1":
+  version: 7.0.1
+  resolution: "@metamask/eth-sig-util@npm:7.0.1"
   dependencies:
     "@ethereumjs/util": ^8.1.0
     "@metamask/abi-utils": ^2.0.2
     "@metamask/utils": ^8.1.0
     ethereum-cryptography: ^2.1.2
-    ethjs-util: ^0.1.6
     tweetnacl: ^1.0.3
     tweetnacl-util: ^0.15.1
-  checksum: bcb6bd23333e0b4dcb49f8772483dcb4c27e75405a2b111f1eafe0b341b221cf86ba4843e91c567d8836e80b6049d8e2f89c6766c62bbd256533e0f256f6d846
+  checksum: 98d056bd83aeb2d29ec3de09cd18e67d97ea295a59d405a9ce3fe274badd2d4f18da1fe530a266b4c777650855ed75ecd3577decd607a561e938dd7a808c5839
   languageName: node
   linkType: hard
 
@@ -3415,7 +3414,7 @@ __metadata:
     "@metamask/eslint-config-jest": ^12.1.0
     "@metamask/eslint-config-nodejs": ^12.1.0
     "@metamask/eslint-config-typescript": ^12.1.0
-    "@metamask/eth-sig-util": ^7.0.0
+    "@metamask/eth-sig-util": ^7.0.1
     "@metamask/keyring-api": ^1.0.0-rc.1
     "@metamask/snaps-cli": ^3.0.0
     "@metamask/snaps-types": ^3.0.0
@@ -11229,16 +11228,6 @@ __metadata:
   languageName: node
   linkType: hard
 
-"ethjs-util@npm:^0.1.6":
-  version: 0.1.6
-  resolution: "ethjs-util@npm:0.1.6"
-  dependencies:
-    is-hex-prefixed: 1.0.0
-    strip-hex-prefix: 1.0.0
-  checksum: 1f42959e78ec6f49889c49c8a98639e06f52a15966387dd39faf2930db48663d026efb7db2702dcffe7f2a99c4a0144b7ce784efdbf733f4077aae95de76d65f
-  languageName: node
-  linkType: hard
-
 "event-emitter@npm:^0.3.5":
   version: 0.3.5
   resolution: "event-emitter@npm:0.3.5"