ci: show h5dump's version; h5rs dump output checked against 1.14.5

dump_matches_h5dump requires byte identity with the h5dump on PATH, and
CI's rust:latest (Debian 13.7) installs hdf5-tools 1.14.5, not the 1.14.6
the test was written against. Ran the whole clawhdf5-tools suite in
rust:latest with Debian's hdf5-tools and pip h5py 3.16.0 (HDF5 2.0.0), as
CI sets it up, with CLAWHDF5_REQUIRE_INTEROP=1: 18 of 18 pass, so the
comparison needs no loosening. The version is now printed in the CI log
so a future Debian update that changes the output is easy to spot.

Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]>

crates/clawhdf5-tools/README.md

@@ -71,7 +71,9 @@ The DDL output is h5dump's: on the test files of `tests/gen_files.py`
 groups; integers of both byte orders, floats, compound with an array member,
 enum, fixed and variable-length strings; soft, external and hard links; a
 named datatype; compact and dense attributes) `h5rs dump` and `h5rs dump -A`
-print the same bytes as h5dump 1.14.6 — `dump_matches_h5dump` in
+print the same bytes as h5dump 1.14.6 and as Debian's h5dump 1.14.5 (the
+`hdf5-tools` package CI installs in `rust:latest`; the whole interop suite
+was run in that image on 2026-09-26) — `dump_matches_h5dump` in
 `tests/h5rs_interop.rs` checks this, and `dump_shows_nul_padding_in_nested_strings`
 that null-padded strings show their NULs (`"a\000b"`) at any depth, as
 h5dump's do. Not covered by those tests: references, opaque, bitfield,