[workspace] Set Jest transformIgnorePatterns to default (#3880)

This PR makes the following changes:
- In `jest.config.base.js` explicitly set `transformIgnorePatterns` to
the default (`['/node_modules/', '\\.pnp\\.[^\\/]+$']`), which will skip
running transforms on node-modules or pnp files. We were overriding the
default with an empty array. Standard practice is to only transform
specific dependencies if there is a need.
- Remove patch for `unicorn-magic` dependency, as it is no longer being
broken by the jest transform.
- Add README to `./patches` explaining how to make a patch using
`patch-package`. This also prevents the `patches` directory from being
removed if there are no patches, breaking the docker build.

Ref: #3871, #3874

jest.config.base.js

@@ -48,7 +48,10 @@ export default (projectDir) => {
             `<rootDir>/${parentFolder}/*/dist`,
             `<rootDir>/${parentFolder}/teraslice-cli/test/fixtures/`
         ],
-        transformIgnorePatterns: [],
+        // do not run transforms on node_modules or pnp files
+        transformIgnorePatterns: [
+            '/node_modules/',
+            '\\.pnp\\.[^\\/]+$'],
         moduleNameMapper: {
             '^(\\.{1,2}/.*)\\.js$': '$1',
         },

patches/README.md

@@ -0,0 +1,25 @@
+# README
+
+The `patches` directory is used to store patches made using [patch-package](https://github.com/ds300/patch-package/blob/master/README.md).
+
+## How to make a patch
+
+### Making patches
+
+First make changes to the files of a particular package in your node_modules folder, then run
+
+```bash
+yarn patch-package package-name
+```
+
+### Nested packages
+
+If you are trying to patch a package at, e.g. node_modules/package/node_modules/another-package you can just put a / between the package names:
+
+```bash
+npx patch-package package/another-package
+```
+
+### Updating patches
+
+Use exactly the same process as for making patches in the first place, i.e. make more changes, run patch-package, commit the changes to the patch file.