MRG: bump version to 4.8.6-dev, post-release (#2877)

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flake.nix

@@ -48,7 +48,7 @@
 
           sourmash = python.buildPythonPackage rec {
             pname = "sourmash";
-            version = "4.8.5";
+            version = "4.8.6-dev";
             format = "pyproject";
 
             src = ./.;

pyproject.toml

@@ -9,7 +9,7 @@ build-backend = 'maturin'
 name = "sourmash"
 description = "tools for comparing biological sequences with k-mer sketches"
 readme = "README.md"
-version = "4.8.5"
+version = "4.8.6-dev"
 
 authors = [
   { name="Luiz Irber", orcid="0000-0003-4371-9659" },