[SPARK-34718][SQL] Assign pretty names to YearMonthIntervalType and DayTimeIntervalType

[MaxGekk]

What changes were proposed in this pull request?

In the PR, I propose to override the typeName() method in YearMonthIntervalType and DayTimeIntervalType, and assign them names according to the ANSI SQL standard:

but keep the type name as singular according existing naming convention for other types.

Why are the changes needed?

To improve Spark SQL user experience, and have readable types in error messages.

Does this PR introduce any user-facing change?

Should not since the types has not been released yet.

How was this patch tested?

By running the modified tests:

$ build/sbt "test:testOnly *ExpressionTypeCheckingSuite"
$ build/sbt "sql/testOnly *SQLQueryTestSuite -- -z windowFrameCoercion.sql"
$ build/sbt "sql/testOnly *SQLQueryTestSuite -- -z literals.sql"

[AmplabJenkins]

Refer to this link for build results (access rights to CI server needed):
https://amplab.cs.berkeley.edu/jenkins//job/SparkPullRequestBuilder/135973/

[AmplabJenkins]

Refer to this link for build results (access rights to CI server needed):
https://amplab.cs.berkeley.edu/jenkins//job/SparkPullRequestBuilder-K8s/40558/

[yaooqinn]

according to the standard，year-month and day-time is italic，so I guess interval here is unnecessary.

[MaxGekk]

1. I haven't found any places in the SQL standard where year-month and day-time are used without the interval(s) word(s).
2. Actual type name is INTERVAL, year-month and day-time just define (sub-)classes of the type.
3. Since the typeName() method is used in error messages, I do believe we should leave interval in type names for readability.

[MaxGekk]

@cloud-fan @dongjoon-hyun @HyukjinKwon Could you review this PR, please.

[dongjoon-hyun]

+1, LGTM. Thank you.
Merged to master.

[HyukjinKwon]

LGTM2

[cloud-fan]

late LGTM