Fix electron app (#1003)

Updates to the latest version of electron and moves the backend-frontend
communication from node-ipc to websockets. This resolves the previous
roadblock regarding `nodeIntegration` .

Done

- Remove node-ipc in favour of websockets. 
- Move file copying out of `preload.js` to avoid importing module `fs`
there
- Bump all electron pacakge versions to the latest
- Added new package for finding open ports as node-ipc is gone
- Tweaked webpack config for above changes


Partially fixes #468

Questions/ Pending:
- Literally every single test fails for me, presumably some issue with
my setup/environment.
- The websocket communication is not using TLS. I'm not sure how to
enable this, or if we even need to as its all local.
- Still need to create the CI for building/deploying but I'm not sure
where start in this regard as i have no exp with it. Presumably we will
need to point the electron auto-updater to the github releases url's. If
people are happy with this PR I will look at adding the CI before its
merged.
- In dev mode only, I have disabled TLS security becuase my docker
container's cert is not signed. I _assume_ this will be true for other
people who spin up the server on thier own hardware. Perhaps I just need
to change my cert to one from letsencrypt or something...

Notes.
I have not touched javascript in eons so my apologies if the commit
trail is a bit fragmented. I tried to keep them fairly contained and
then there is a slightly gnarly final commit fixing all the linter
issues... Please let me know if you want me to squash some commits etc.

I initially tried to move this to web workers the same way the web app
does it but this was unsuccessful. I have found no way to spin up a
worker in one place (frontend/backend) and then pass this worker to the
other. The electron ipc channels don't allow you to directly pass
objects such as workers, everything is cloned/serialised. Passing a port
number so the other end can spin up its own socket works fine.

---------

Co-authored-by: Shazib Hussain <contact@shazib.com>
Co-authored-by: Jed Fox <git@jedfox.com>

.github/workflows/build.yml

@@ -45,20 +45,26 @@ jobs:
           name: actual-web
           path: packages/desktop-client/build
 
-  # TODO: re-enable after solving https://github.com/actualbudget/actual/issues/468
-  # electron:
-  #   # As electron builds take longer, we only run them in master.
-  #   if: github.event_name != 'pull_request'
-  #   strategy:
-  #     matrix:
-  #       os:
-  #         - ubuntu-latest
-  #         - windows-latest
-  #         - macos-latest
-  #   runs-on: ${{ matrix.os }}
-  #   steps:
-  #     - uses: actions/checkout@v3
-  #     - name: Set up environment
-  #       uses: ./.github/actions/setup
-  #     - name: Build Electron
-  #       run: ./bin/package
+  electron:
+    # As electron builds take longer, we only run them in master.
+    strategy:
+      matrix:
+        os:
+          - ubuntu-latest
+          - windows-latest
+          - macos-latest
+    runs-on: ${{ matrix.os }}
+    steps:
+      - uses: actions/checkout@v3
+      - name: Set up environment
+        uses: ./.github/actions/setup
+      - name: Build Electron
+        run: ./bin/package-electron
+      - name: Upload Build
+        uses: actions/upload-artifact@v3
+        with:
+          name: actual-electron-${{ matrix.os }}
+          path: |
+            packages/desktop-electron/dist/*.dmg
+            packages/desktop-electron/dist/*.exe
+            packages/desktop-electron/dist/*.AppImage