Update fancy-regex to v0.13.0

After this update clippy began to warn about the size of the `TokenizerError`
enum due to changes in `fancy_regex::Error`. To resolve this, box the value.

rten-text/Cargo.toml

@@ -13,7 +13,7 @@ include = ["/src", "/README.md"]
 crate-type = ["lib"]
 
 [dependencies]
-fancy-regex = { version = "0.12.0", default-features = false, features = ["std", "unicode"] }
+fancy-regex = { version = "0.13.0", default-features = false, features = ["std", "unicode"] }
 unicode_categories = "0.1.1"
 unicode-normalization = "0.1.22"
 serde = { workspace = true, features = ["derive"] }

rten-text/src/tokenizers.rs

@@ -595,7 +595,7 @@ pub enum TokenizerError {
     InvalidTokenId(TokenId),
 
     /// Splitting the input with a regex failed.
-    RegexSplitFailed(fancy_regex::Error),
+    RegexSplitFailed(Box<fancy_regex::Error>),
 
     /// There was an error parsing a byte sequence as a UTF-8 string.
     ///

rten-text/src/tokenizers/bpe.rs

@@ -18,7 +18,7 @@ pub enum BpeError {
     InvalidMergeEntry(String),
 
     /// The regex for splitting tokens is invalid.
-    InvalidPattern(fancy_regex::Error),
+    InvalidPattern(Box<fancy_regex::Error>),
 
     /// An entry in the vocab (token string to ID map) is not either a known
     /// special token or an entry in the merge list.
@@ -289,7 +289,7 @@ impl Bpe {
         vocab: Option<HashMap<EncodedBytes, TokenId>>,
         added_tokens: HashMap<TokenId, String>,
     ) -> Result<Bpe, BpeError> {
-        let splitter = Regex::new(pattern).map_err(BpeError::InvalidPattern)?;
+        let splitter = Regex::new(pattern).map_err(|err| BpeError::InvalidPattern(err.into()))?;
 
         let mut builder = BpeBuilder::new();
         builder.add_merges(merges)?;
@@ -428,7 +428,7 @@ impl Encoder for Bpe {
         on_token: &mut dyn FnMut(usize, TokenId),
     ) -> Result<(), TokenizerError> {
         for piece in self.splitter.find_iter(text) {
-            let piece = piece.map_err(TokenizerError::RegexSplitFailed)?;
+            let piece = piece.map_err(|err| TokenizerError::RegexSplitFailed(err.into()))?;
             if piece.range().is_empty() {
                 continue;
             }