Add ENABLE_WARMUP parameter

[lorisleitner]

I added the parameter ENABLE_WARMUP to the start.sh script.

This new parameter allows skipping the database warmup routine after the container restarts.
Useful for answering requests immediately after the container starts.

Default value is true for backwards compatibility.

[what-the-diff]

PR Summary

• Updated README.md document
  The README.md file now includes additional details about a new environment variable called ENABLE_WARMUP. This variable is used to manage the system's database warmup behavior and is by default set to 'true.'

• Improved example.md document
  The example.md document has a new entry referring to the ENABLE_WARMUP variable. This entry offers direction to users, informing them that the variable can be assigned either a 'true' or 'false' value based on their preferences.

• Restructured start.sh script

  • A new decision-making logic segment has been implemented. This routine checks the status of the ENABLE_WARMUP variable. If the variable is either unassigned or set to 'true,' a database warmup operation is initiated. If it is set to 'false,' the operation is skipped.
  • There has been an adjustment in the request time out and query settings, dependent on whether a warmup operation is carried out.

[leonardehrenfried]

Looks good but would you be able to add a test for this?

It's fine to disable it for 4.4.