Update pypdf to version 6.7.1 in environment files

docs/environment_files/gcpy_environment_py312.yml
docs/environment_files/gcpy_environment_py313.yml
- Update pypdf to version 6.7.1

CHANGELOG.md
- Updated accordingly

Signed-off-by: Bob Yantosca <yantosca@seas.harvard.edu>

Author: yantosca

CHANGELOG.md

@@ -4,6 +4,10 @@ All notable changes to GCPy will be documented in this file.
 
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/), and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## [Unreleased] - TBD
+### Changed
+- Bumped `pypdf` to version 6.7.1 in `setup.py` and environment files
+
 ## [1.7.1] - 2026-02-03
 ### Changed
 - Bumped `pip` to version 26.0 in `setup.py` and environment files

docs/environment_files/gcpy_environment_py312.yml

@@ -30,7 +30,7 @@ dependencies:
   - pylint         ==3.2.2      # Python linter
   - pyproj         ==3.6.1      # Python map projections library
   - python         ==3.12.0     # Python language
-  - pypdf          ==6.6.2      # PDF utilities (bookmarks, etc.)
+  - pypdf          ==6.7.1      # PDF utilities (bookmarks, etc.)
   - requests       ==2.32.4     # HTTP library
   - scipy          ==1.13.1     # Scientific python package
   - sparselt       ==0.1.3      # Regridding earth system model data

docs/environment_files/gcpy_environment_py313.yml

@@ -30,7 +30,7 @@ dependencies:
   - pylint         ==3.3.4      # Python linter
   - pyproj         ==3.7.1      # Python map projections library
   - python         ==3.13       # Python language
-  - pypdf          ==6.6.2      # PDF utilities (bookmarks, etc.)
+  - pypdf          ==6.7.1      # PDF utilities (bookmarks, etc.)
   - requests       ==2.32.4     # HTTP library
   - scipy          ==1.15.2     # Scientific python package
   - sparselt       ==0.1.3      # Regridding earth system model data