message: Update: `signer-ethers` package version
diff: {
  "name": "@purser/signer-ethers",
  - "version": "1.0.1-alpha.0",
  + "version": "1.0.1",
  "description": "A signer to use purser with ethers.js",
  "license": "MIT",
  "main": "lib/index.js",
  