[BUG] the generated gradlew file does not have the correct permission

Created by: jmini

The gradlew file in the generated project (like in samples/) is wrong.

If you run .gradlew build in samples/client/petstore/java/okhttp-gson you get:

-bash: ./gradlew: Permission denied

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Workaround: run chmod +x gradlew before starting gradle.

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I think gradlew is a supporting file. We probably need something like this after generation.

private void setExecutable(Path file) throws IOException {
    Set<PosixFilePermission> perms = new HashSet<PosixFilePermission>();
    //add owners permission
    perms.add(PosixFilePermission.OWNER_READ);
    perms.add(PosixFilePermission.OWNER_WRITE);
    perms.add(PosixFilePermission.OWNER_EXECUTE);
    //add group permissions
    perms.add(PosixFilePermission.GROUP_READ);
    //add others permissions
    perms.add(PosixFilePermission.OTHERS_READ);
    Files.setPosixFilePermissions(Paths.get(file).getAbsolutePath()), perms);
}