[Autocomplete] Ensure default plugins are nicely merged with user-defined plugins

[Kocal]

Q	A
Bug fix?	yes
New feature?	no
Docs?	no
Issues	Fix #1128, Fix #2002
License	MIT

The issue happens because when merging the default configuration and the configuration defined by the user, plugins defined by the users erase plugins defined in the default configuration:

At the moment, when the user didn't define tom_select_options.plugins, everything works fine:

Screenshot

But when configuring tom_select_options.plugins, some necessary plugins are missing:

Screenshot

With this PR, tom_select_options.plugins from the default configuration and the configuration defined by the user are nicely merged:

Screenshots

TODO:

• Update JS tests to prevent regressions

[github-actions]

📊 Packages dist files size difference

Thanks for the PR! Here is the difference in size of the packages dist files between the base branch and the PR.
Please review the changes and make sure they are expected.

File	Before (Size / Gzip)	After (Size / Gzip)
Autocomplete
controller.js	16.7 kB / 3.96 kB	17.6 kB+5% 📈 / 4.12 kB+4% 📈

[Kocal]

This test fails (as expected), when running on 2.x:

⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯ Unhandled Errors ⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯

Vitest caught 1 unhandled error during the test run.
This might cause false positive tests. Resolve unhandled errors to make sure your tests are not affected.

⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯ Uncaught Exception ⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯
TypeError: this.getUrl is not a function
 ❯ TomSelect.call src/controller.ts:264:34
    262|             // the 'this.XXX' calls inside this method fail
    263|             load: function (query: string, callback: TomLoadCallback) {
    264|                 const url = this.getUrl(query);
       |                                  ^
    265|                 fetch(url)
    266|                     .then((response) => response.json())
 ❯ Timeout._onTimeout ../../../node_modules/tom-select/src/utils.ts:59:7
 ❯ listOnTimeout node:internal/timers:594:17
 ❯ processTimers node:internal/timers:529:7

This error originated in "test/controller.test.ts" test file. It doesn't mean the error was thrown inside the file itself, but while it was running.
The latest test that might've caused the error is "connect with ajax URL on a select element, even when the user defined custom TomSelect plugin". It might mean one of the following:
- The error was thrown, while Vitest was running this test.
- If the error occurred after the test had been completed, this was the last documented test before it was thrown.

[Kocal]

Converting ['foo'] or [{ name: 'foo', options: {/* ... */} }] to { foo: {/* ... */} } helps us to merge the plugins configurations