Update Express v5

[alexandercerutti]

Description

This Pull Request attempts upgrading to Express v5 (#1691).
I run all the tests, linting and build. Everything passed fine.
I cannot test - if test are not available - the integration with Apollo GraphQL.

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[gemini-code-assist]

Code Review

This pull request upgrades the project's dependencies to Express v5 and Chai v5. Key changes include updating package.json and package-lock.json, migrating to @as-integrations/express5, and refactoring tests to use res.sendStatus() instead of passing numeric status codes to res.send(), which is a breaking change in Express v5. Feedback suggests that the sendStatus implementation in the MockResponse helper should be adjusted to send the status code as a string in the response body to accurately reflect Express v5 behavior.

[gemini-code-assist]

The sendStatus implementation in MockResponse should ideally send the status code as the response body to match Express v5 behavior, e.g., this.send(code.toString()).

Suggested change

	public sendStatus(code: number) {
	this.status(code);
	this.end();
	}
	public sendStatus(code: number) {
	this.status(code);
	this.send(code.toString());
	}

[alexandercerutti]

I'm not really sure about this.
.send shouldn't accept anymore the status in Express v5, so I change the mock as well to complete the request. (or, yes, make the code a string, but I'm not sure it still make sense)