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## Environment
**Liquibase Version**: 3.10

**Database Vendor & Version**: any

**Operating System Type & Version**: any

## Description
Create a custom change with a params list where there is no "name", it will trigger a NullPointerException instead of a nicer validation error explaining the problem.

## Steps To Reproduce
A changelog file with the following customChange:

```
     - customChange:
         class: com.company.customchanges.AddAttribute
         param:
           fieldType: '12'
           mandatory: '1'
           labelKey: userAttribute.firstName
           maxLength: '50'
           index: '2'
           newline: '1'
           readOnly: '1'
           visible: '1'
```

which **was generated by the Liquibase YamlChangelogSerializer!!** (which is a separate issue)
trriggered a NullPointerException.

## Actual Behavior
A NullPointerException without a message.

## Expected/Desired Behavior
A clearer validation error should be thrown indicating the cause of the problem.


} catch (CustomChangeException e) {
            throw new UnexpectedLiquibaseException(e);
        }
        return customChange.getConfirmationMessage();
    }
    private void configureCustomChange() throws CustomChangeException {
        if (configured) {
            return;
        }
        try {
            for (String param : params) {
                ObjectUtil.setProperty(customChange, param, paramValues.get(param));
            }
            customChange.setFileOpener(Scope.getCurrentScope().getResourceAccessor());
            customChange.setUp();
            configured = true;
        } catch (Exception e) {
            throw new CustomChangeException(e);
        }
    }
    @Override
    public SerializationType getSerializableFieldType(String field) {
        switch (field) {
            case "class":
                return SerializationType.NAMED_FIELD;
            case "param":
                return SerializationType.NAMED_FIELD;
            default:
                throw new UnexpectedLiquibaseException("Unexpected CustomChangeWrapper field " + field);
        }