chore(nodejs): Update to active LTS v20 (#2011)

* chore(nodejs): Use active LTS v20 for nodejs

This updates nodejs to use the active LTS v20 from the maintenance LTS
v18.  This expands compatibility with packages, adds native support for
more features, etc.

In addition, the ci-seed-chain workflow was updated to use the
.tool-version file instead of hardcoded version.

* chore(hardhat): Update hardhat for nodejs 20 support

.github/workflows/cd-seed-chain.yml

@@ -72,7 +72,7 @@ jobs:
         uses: actions/setup-node@v3
         with:
           cache: npm
-          node-version: 18
+          node-version-file: .tool-versions
           cache-dependency-path: kava-bridge/contract/package.json
       - name: "install ERC20 contract deployment dependencies"
         run: "npm install"

.tool-versions

@@ -1,2 +1,2 @@
 golang 1.21.9
-nodejs 18.16.0
+nodejs 20.16.0

contracts/package.json

@@ -5,7 +5,7 @@
   "private": true,
   "description": "Solidity contracts for Kava Blockchain",
   "engines": {
-    "node": ">=18.0.0"
+    "node": ">=20.0.0"
   },
   "scripts": {
     "build": "npm run clean && npm run compile && npm run ethermint-json",
@@ -23,14 +23,14 @@
     "test": "hardhat test"
   },
   "devDependencies": {
-    "@nomicfoundation/hardhat-toolbox": "^2.0.2",
+    "@nomicfoundation/hardhat-toolbox": "^5.0.0",
     "@openzeppelin/contracts": "4.8.3",
     "@typescript-eslint/eslint-plugin": "^5.59.6",
     "@typescript-eslint/parser": "^5.59.6",
     "eslint": "^8.40.0",
     "eslint-config-prettier": "8.8.0",
     "eslint-plugin-prettier": "^4.2.1",
-    "hardhat": "^2.14.0",
+    "hardhat": "^2.22.8",
     "prettier": "2.8.8",
     "prettier-plugin-solidity": "^1.1.3",
     "solhint": "^3.4.1",