tree-sitter: unquote latest version in update script

Otherwise if a tag was found it would try to fetch `refs/tag/"v1.2.0"`.

```
fetching list of grammars
checking the tree-sitter repo list against the grammars we know
writing files to /etc/nixos/nixpkgs/pkgs/development/tools/parsing/tree-sitter/grammars
Fetching latest release ("v1.2.1") of tree-sitter-agda …
Initialized empty Git repository in /tmp/git-checkout-tmp-RU9DUpjM/tree-sitter-agda/.git/
fatal: couldn't find remote ref refs/tags/"v1.2.1"
From https://github.com/tree-sitter/tree-sitter-agda
 * branch            HEAD       -> FETCH_HEAD
fatal: Not a valid object name
Unrecognized git object type:
Unable to checkout refs/tags/"v1.2.1" from https://github.com/tree-sitter/tree-sitter-agda.
```

pkgs/development/tools/parsing/tree-sitter/update.nix

@@ -380,7 +380,7 @@ let
     if [[ "$(printf "%s" "$res" | ${jq}/bin/jq '.message?')" =~ "rate limit" ]]; then
       echo "rate limited" >&2
     fi
-    release="$(printf "%s" "$res" | ${jq}/bin/jq -r '.tag_name')"
+    release="$(printf "%s" "$res" | ${jq}/bin/jq -r '.tag_name' | tr -d \")"
     # github sometimes returns an empty list even tough there are releases
     if [ "$release" = "null" ]; then
       echo "uh-oh, latest for ${orga + "/" + repo} is not there, using HEAD" >&2