Support pcodec v0.3 (#639)

* support delta_spec and paging_spec

* coverage, try to fix zarr v3

* explicitly test try_consecutive

* delta_spec default of auto

* pcodec upper bound

* revert zarr test change

* test parameterize, match cases

* docstring and matching cleanup

* add release notes

---------

Co-authored-by: David Stansby <dstansby@gmail.com>

Author: slevang

docs/release.rst

@@ -0,0 +1,9 @@
+{
+    "delta_encoding_order": 2,
+    "delta_spec": "auto",
+    "equal_pages_up_to": 262144,
+    "id": "pcodec",
+    "level": 8,
+    "mode_spec": "auto",
+    "paging_spec": "equal_pages_up_to"
+}