Slog with Groups and Attributes

[mirackara]

Builds on-top of #987

• Support for transactions in context

	txn := app.StartTransaction("test")
	ctx := newrelic.NewContext(context.Background(), txn)
	logger.InfoContext(ctx, "log has tracing on new relic")
	txn.End()

• Corrected Grouping and Attributes System (Either Method Works)

logger.WithGroup("program_info").With("pid", os.Getpid()).Info("log message with group and attribute")

logger.Info("I am a log group inside a log message",
	slog.Group("logGroup",
		slog.String("key1", "val"),
		slog.Int("key2", 1),
	),
)

[mirackara]

Still Working on this - Updated the example main.go to show what is currently supported.

There are some bugs that still need squashing

• Issue with Attributes in the LogWithGroupAttributes example being Duplicated
• Issue with Attributes in the logWithLogAttrs example showing up correctly with their groups on nr1, but not in the log