[SPARK-24757][SQL] Improving the error message for broadcast timeouts

[MaxGekk]

What changes were proposed in this pull request?

In the PR, I propose to provide a tip to user how to resolve the issue of timeout expiration for broadcast joins. In particular, they can increase the timeout via spark.sql.broadcastTimeout or disable the broadcast at all by setting spark.sql.autoBroadcastJoinThreshold to -1.

How was this patch tested?

It tested manually from spark-shell:

scala> spark.conf.set("spark.sql.broadcastTimeout", 1)
scala> val df = spark.range(100).join(spark.range(15).as[Long].map { x =>
               Thread.sleep(5000)
               x
            }).where("id = value")
scala> df.count()

org.apache.spark.SparkException: Could not execute broadcast in 1 secs. You can increase the timeout for broadcasts via spark.sql.broadcastTimeout or disable broadcast join by setting spark.sql.autoBroadcastJoinThreshold to -1
  at org.apache.spark.sql.execution.exchange.BroadcastExchangeExec.doExecuteBroadcast(BroadcastExchangeExec.scala:150)

[MaxGekk]

@hvanhovell Please, have a look at the PR.

[SparkQA]

Test build #92712 has finished for PR 21727 at commit 86587ed.

• This patch passes all tests.
• This patch merges cleanly.
• This patch adds no public classes.

[hvanhovell]

LGTM

[hvanhovell]

Merging to master. Thanks!