* adding a configuration for disabling auto-instrumentations
addressing review feedback from pdelewski, provide a mechanism that can be used to disable auto-instrumentation packages
without actually uninstalling them.
A new variable, OTEL_PHP_DISABLED_INSTRUMENTATIONS, has been added which accepts a list of instrumentation names to be disabled.
Each instrumentation can call Instrumentation::isDisabled to determine if they should bail without registering hooks.
* moving instrumentation disabled into Sdk class
Brett McBride