fix(build): bugfix npm package

Remove packages from build due to npm using `files` path in any `package.json` it sees.

fixup.sh

@@ -0,0 +1,11 @@
+#!/bin/sh
+
+package_version=`npm show . version`
+
+for target in esm cjs; do
+    cat >build/$target/package.json <<!EOF
+{
+    "version": "$package_version"
+}
+!EOF
+done

package.json

@@ -21,7 +21,7 @@
     "test": "npm run test:unit",
     "build": "tsc -p tsconfig-esm.json && tsc -p tsconfig-cjs.json",
     "clean": "rm -rf build",
-    "prepublish": "npm run clean && npm run build",
+    "prepublish": "npm run clean && npm run build && ./fixup.sh",
     "release": "standard-version"
   },
   "keywords": [

tsconfig-base.json

@@ -23,6 +23,7 @@
     "certs"
   ],
   "exclude": [
-    "node_modules"
+    "node_modules",
+    "package.json"
   ]
 }