[Java] fix LocalTime import for dateLibrary java8

Created by: Crydust

The import mapping for LocalTime still pointed to org.joda.time.*. This one line made the jodatime dependency required.

I've added it where @cbornet had already placed the code for LocalDate.

Without this change I've had to resort to this workaround in my build:

<plugin>
    <artifactId>maven-antrun-plugin</artifactId>
    <version>3.1.0</version>
    <executions>
        <execution>
            <phase>generate-sources</phase>
            <goals>
                <goal>run</goal>
            </goals>
            <configuration>
                <target>
                    <replace
                            dir="${project.build.directory}/generated-sources/openapi/src/main/java"
                            includes="**/*.java"
                            token="import org.joda.time.*;"
                            value="/* do not import jodatime */"/>
                </target>
            </configuration>
        </execution>
    </executions>
</plugin>

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