ESM Support (#3978)

* ESM changes

* Fix root lodestar script

* Fix some linter errors

* trying directly re-exporting under an alias from networks module

* Fix types exports

* Fix more linter errors

* Fix spec test download

* Update bls to 7.1.0

* Fix spec tests

* temp reverting eslint parser option to 10 and disabling the check of .js file extenstion. Should fix lint errors

* temp commented out file-extension-in-import

* Disable readme checks

* Fix check-build

* Fix params e2e tests

* Bump @chainsafe/threads

* Bump bls to v7.1.1

* Add timeouts after node initialization but before sim test run

* Tweak timeouts

* Tweak timeout

* Tweak sim merge timeout

* Tweak sim merge timeout

* Tweak sim merge timeout

* Tweak sim merge timeout

* Add more timeouts

* Add another timeout

* Fix linter errors

* Fix some tests

* Fix some linter errors and spec tests

* Fix benchmarks

* Fix linter errors

* Update each bls dependency

* Tweak timeouts

* Add another timeout

* More timeouts

* Fix bls pool size

* Set root package.json to ESM

* Remove old linter comment

* Revert "Set root package.json to ESM"

This reverts commit 347b0fdd18.

* Remove stray file (probably old)

* Undo unnecessary diff

* Add comment on __dirname replacement

* Import type @chainsafe/bls/types

* Use lodestar path imports

* Revert multifork to lodestar package

* Format .mocharc.yaml

* Use same @chainsafe/as-sha256 version

* Fix lodash path imports

* Use src instead of lib

* Load db metrics

* Remove experimental-specifier-resolution

* Remove lodestat/chain export

* Add stray missing file extension

* Revert ValidatorDir changes

* Fix stray missing file extensions

* Fix check-types

Co-authored-by: Dadepo Aderemi <dadepo@gmail.com>
Co-authored-by: dapplion <35266934+dapplion@users.noreply.github.com>

tsconfig.build.json

@@ -1,10 +1,12 @@
 {
   "compilerOptions": {
     "target": "es2019",
-    "module": "commonjs",
-    "pretty": true,
     "lib": ["es2020", "esnext.bigint", "es2020.string", "es2020.symbol.wellknown"],
 
+    "module": "esnext",
+    "moduleResolution": "node",
+
+    "pretty": true,
     "strict": true,
     "sourceMap": true,
     "alwaysStrict": true,