function findAllVersions(toolName, arch) {
    const versions = [];
    arch = arch || os.arch();
    const toolPath = path.join(_getCacheDirectory(), toolName);
    if (fs.existsSync(toolPath)) {
        const children = fs.readdirSync(toolPath);
        for (const child of children) {
            if (isExplicitVersion(child)) {
                const fullPath = path.join(toolPath, child, arch || '');
                if (fs.existsSync(fullPath) && fs.existsSync(`${fullPath}.complete`)) {
                    versions.push(child);
                }
            }
        }
    }
    return versions;
}
Finds the paths to all versions of a tool that are installed in the local tool cache

@param toolName  name of the tool
@param arch      optional arch.  defaults to arch of computer