Lazy load GlobalOpenTelemetry

[gastaldi]

There are cases where the Global OpenTelemetry may not have been initialized yet, so it's better to initialize lazily

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[gastaldi]

This doesn't solve the problem, because the OpenTelemetry API is called when the JDBC connection is created:

22:09:34,972 INFO  [app] java.lang.Exception: Stack trace
22:09:34,972 INFO  [app] 	at java.base/java.lang.Thread.dumpStack(Thread.java:2210)
22:09:34,972 INFO  [app] 	at com.mysql.cj.otel.OpenTelemetryHandler.getOpenTelemetry(OpenTelemetryHandler.java:84)
22:09:34,972 INFO  [app] 	at com.mysql.cj.otel.OpenTelemetryHandler.getTracer(OpenTelemetryHandler.java:92)
22:09:34,972 INFO  [app] 	at com.mysql.cj.otel.OpenTelemetryHandler.startSpan(OpenTelemetryHandler.java:51)
22:09:34,973 INFO  [app] 	at com.mysql.cj.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:359)
22:09:34,973 INFO  [app] 	at com.mysql.cj.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:237)
22:09:34,973 INFO  [app] 	at com.mysql.cj.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:180)
22:09:34,973 INFO  [app] 	at io.agroal.pool.ConnectionFactory.createConnection(ConnectionFactory.java:225)