Only run "Arduino IDE" workflow on relevant changes

The "Arduino IDE" workflow performs the following operations when triggered on push and pull request events:

- Build application
- Lint code
- Run tests
- Produce tester packages

All of these operations are specific to the TypeScript/JavaScript code base and its infrastructure.

Previously, the workflow ran whenever any file in the repository was changed. This includes files that have no
relevance, meaning the operations performed by the workflow were pointless. In addition to general inefficiency, these
lengthy and sometimes spuriously failing unnecessary workflow runs might cause delay or confusion to both the
contributors and maintainers for what would otherwise be a simple process.

GitHub Actions provides the ability to configure path filters for the workflow triggers. The workflow will only run on
events that change files satisfying these path filters. This is "AND"ed with the `branches` filters, meaning the existing
restrictions on which branches produce a run remain unchanged. The `tags` filter is independent from the `paths` and
`branches` filters, meaning the added path filters don't make any change to which tag push events will trigger the
workflow.

Author: per1234

.github/workflows/build.yml

@@ -4,10 +4,26 @@ on:
   push:
     branches:
       - main
+    paths-ignore:
+      - '.github/**'
+      - '!.github/workflows/build.yml'
+      - '.vscode/**'
+      - 'docs/**'
+      - 'scripts/**'
+      - 'static/**'
+      - '*.md'
     tags:
       - '[0-9]+.[0-9]+.[0-9]+*'
   workflow_dispatch:
   pull_request:
+    paths-ignore:
+      - '.github/**'
+      - '!.github/workflows/build.yml'
+      - '.vscode/**'
+      - 'docs/**'
+      - 'scripts/**'
+      - 'static/**'
+      - '*.md'
   schedule:
     - cron: '0 3 * * *' # run every day at 3AM (https://docs.github.com/en/actions/reference/events-that-trigger-workflows#scheduled-events-schedule)