[JavascriptFlowtyped] snapshot property

Created by: SixYearsInFebruary

if (additionalProperties.containsKey(SNAPSHOT) && Boolean.valueOf(additionalProperties.get(SNAPSHOT).toString())) {
     this.setNpmVersion(npmVersion + "-SNAPSHOT." + SNAPSHOT_SUFFIX_FORMAT.format(new Date()));
}

If the version in pom.xml is x.x.x-SNAPSHOT, the config of openapi-generator-maven-plugin like below:

<additionalProperty>npmVersion=${project.version}</additionalProperty>
<additionalProperty>snapshot=true</additionalProperty>

the generate code in package.json will be x.x.x-SNAPSHOT-SHAPSHOT.yyyyMMddHHmm. May be, if the version contains SNAPSHOT, should not append -SNAPSHOT to it again.