### What changes were proposed in this pull request?
This PR modified the parser code to handle invalid usages of a SET/RESET command.
For example;
```
SET spark.sql.ansi.enabled true
```
The above SQL command does not change the configuration value and it just tries to display the value of the configuration
`spark.sql.ansi.enabled true`. This PR disallows using special characters including spaces in the configuration name and reports a user-friendly error instead. In the error message, it tells users a workaround to use quotes or a string literal if they still needs to specify a configuration with them.
Before this PR:
```
scala> sql("SET spark.sql.ansi.enabled true").show(1, -1)
+---------------------------+-----------+
|key |value |
+---------------------------+-----------+
|spark.sql.ansi.enabled true|<undefined>|
+---------------------------+-----------+
```
After this PR:
```
scala> sql("SET spark.sql.ansi.enabled true")
org.apache.spark.sql.catalyst.parser.ParseException:
Expected format is 'SET', 'SET key', or 'SET key=value'. If you want to include special characters in key, please use quotes, e.g., SET `ke y`=value.(line 1, pos 0)
== SQL ==
SET spark.sql.ansi.enabled true
^^^
```
### Why are the changes needed?
For better user-friendly errors.
### Does this PR introduce _any_ user-facing change?
No.
### How was this patch tested?
Added tests in `SparkSqlParserSuite`.
Closes#29146 from maropu/SPARK-32257.
Lead-authored-by: Takeshi Yamamuro <yamamuro@apache.org>
Co-authored-by: Wenchen Fan <wenchen@databricks.com>
Signed-off-by: Wenchen Fan <wenchen@databricks.com>
c6109ba918