chore: remove use of "err" a log line context key for errors. (#14433)

Log lines which include an error should use the full term "error"
as the context key. This provides consistency across the codebase
and avoids a Go style which operators might not be aware of.

drivers/java/driver.go

@@ -636,7 +636,7 @@ func (d *Driver) DestroyTask(taskID string, force bool) error {
 
 	if !handle.pluginClient.Exited() {
 		if err := handle.exec.Shutdown("", 0); err != nil {
-			handle.logger.Error("destroying executor failed", "err", err)
+			handle.logger.Error("destroying executor failed", "error", err)
 		}
 
 		handle.pluginClient.Kill()