Activate build of `ba-dua-example` with Java 9
Activate build of `ba-dua-example` with Java 9

On PR #22 (20f2dfe) I wrongly didn't activate build of module
`ba-dua-example` for all Java 9 versions.

See that Java 9 builds does not include module `ba-dua-example`
* [Windows](https://github.com/saeg/ba-dua/runs/3628430481)
* [Linux](https://github.com/saeg/ba-dua/runs/3628430233)

(I hope GitHub keep these links in the future)

Quoting Maven documentation:
> an upper bound such as `,1.5]` is likely not to include most releases of
> 1.5, since they will have an additional "patch" release such as `_05`
> that is not taken into consideration in the above range.

This commit fix the supported version range.

saeg/ba-dua