Write the PHP-FPM timeout message on a single line

[mnapoli]

When a PHP-FPM request times out, Bref writes a message made of 3 lines. Lambda turns each line written to stdout into a separate log event, so it became 3 CloudWatch events with the same timestamp, and only the first one started with the request ID:

092cf7a5-0989-4e24-9d83-5044cb3c8dda The PHP script timed out. Bref will now restart PHP-FPM to start from a clean slate and flush the PHP logs.
Timeouts can happen for example when trying to connect to a remote API or database, if this happens continuously check for those.
If you are using a RDS database, read this: https://bref.sh/docs/environment/database.html#accessing-the-internet

Searching the logs of a request (e.g. filter @requestId = '…' in CloudWatch Logs Insights, see "Logs of a single request" in the logs documentation) returned only the first line, not the two explanatory ones, and since the 3 events share a timestamp, log viewers could show them out of order.

This writes the same text on a single line. It also fixes the link: the #accessing-the-internet anchor no longer exists, the section is now "VPC databases (private network)".

Also the AWS SDK has a "recursion detection" step that adds an X-Amzn-Trace-Id header to AWS calls when _X_AMZN_TRACE_ID is set. In FPM that now happens, as it already did in the worker and console runtimes.