[hotfix][Table SQL / API] fix create table from values decimal issue

[empathy87]

What is the purpose of the change

The following code fails on the second fromValues:

List<Row> rows1 = new ArrayList<>();
rows1.add(Row.of(new BigDecimal("1.01")));
final Table table1 = tableEnv().fromValues(rows1);
List<Row> rows2 = new ArrayList<>();
rows2.add(Row.of(new BigDecimal("0.01")));
final Table table2 = tableEnv().fromValues(rows2);

with an exception

org.apache.flink.table.api.ValidationException: Decimal scale must be between 0 and the precision 1 (both inclusive).

	at org.apache.flink.table.types.logical.DecimalType.<init>(DecimalType.java:76)
	at org.apache.flink.table.types.logical.DecimalType.<init>(DecimalType.java:85)
	at org.apache.flink.table.api.DataTypes.DECIMAL(DataTypes.java:283)
	at org.apache.flink.table.types.utils.ValueDataTypeConverter.convertToDecimalType(ValueDataTypeConverter.java:131)
	at org.apache.flink.table.types.utils.ValueDataTypeConverter.extractDataType(ValueDataTypeConverter.java:69)
	at org.apache.flink.table.expressions.ValueLiteralExpression.deriveDataTypeFromValue(ValueLiteralExpression.java:354)

The reason is that the object new BigDecimal("0.01") has scale = 2 and precision = 1, which is not appropriate for Flink Decimal type. So, Flink Decimal type creation from BigDecimal value should be adjusted.

Brief change log

• Added precision adjustment in ValueDataTypeConverter::convertToDecimalType to reflect that BigDecimal could have precision less than scale

Verifying this change

This change is a trivial rework / code cleanup without any test coverage.

Does this pull request potentially affect one of the following parts:

• Dependencies (does it add or upgrade a dependency): (yes / no)
• The public API, i.e., is any changed class annotated with @Public(Evolving): (yes / no)
• The serializers: (yes / no / don't know)
• The runtime per-record code paths (performance sensitive): (yes / no / don't know)
• Anything that affects deployment or recovery: JobManager (and its components), Checkpointing, Kubernetes/Yarn, ZooKeeper: (yes / no / don't know)
• The S3 file system connector: (yes / no / don't know)

Documentation

• Does this pull request introduce a new feature? (yes / no)
• If yes, how is the feature documented? (not applicable / docs / JavaDocs / not documented)

[flinkbot]

CI report:

• bdb7628 Azure: SUCCESS

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[dylanhz]

LGTM