Release 0.13.3

For some reason under a docker build I get a build error under docker only saying that `serde::export` is private. This fixes it for me.

```
error[E0603]: module `export` is private
   --> /usr/local/cargo/registry/src/github.com-1ecc6299db9ec823/tantivy-0.13.2/src/collector/top_collector.rs:5:12
    |
5   | use serde::export::PhantomData;
    |            ^^^^^^ private module
    |
note: the module `export` is defined here
   --> /usr/local/cargo/registry/src/github.com-1ecc6299db9ec823/serde-1.0.119/src/lib.rs:275:5
    |
275 | use self::__private as export;
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^
```

CHANGELOG.md

@@ -1,3 +1,7 @@
+Tantivy 0.13.3
+======================
+Bugfix. Avoid relying on serde's reexport of PhantomData. (#975)
+
 Tantivy 0.13.2
 ===================
 Bugfix. Acquiring a facet reader on a segment that does not contain any 

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "tantivy"
-version = "0.13.2"
+version = "0.13.3"
 authors = ["Paul Masurel <paul.masurel@gmail.com>"]
 license = "MIT"
 categories = ["database-implementations", "data-structures"]

src/collector/top_collector.rs

@@ -2,7 +2,7 @@ use crate::DocAddress;
 use crate::DocId;
 use crate::SegmentLocalId;
 use crate::SegmentReader;
-use serde::export::PhantomData;
+use std::marker::PhantomData;
 use std::cmp::Ordering;
 use std::collections::BinaryHeap;