Bump version to v2.9.1

[vicentebolea]

#3718

Backports

PR	Title
#3676	Version constants plus functions to retrieve list of ...
#3697	build(deps): bump cryptography from 41.0.0 to 41.0.2 in /docs
#3698	added gitattributes file
#3704	build(deps): bump pygments from 2.14.0 to 2.15.0 in /docs
#3712	build(deps): bump certifi from 2022.12.7 to 2023.7.22 in /docs
#3687	Fix for the issue #3646.
#3699	Update files with new EOL
#3690	Merge pull request #3689 from vicentebolea/fix-evpath-modules
#3689	cmake,evpath: namespace modules install dir
#3684	Fix memory leak when there are Joined Arrays in streaming mode
#3652	work around with include <unistd.h> on windows
#3650	Bump cryptography from 39.0.1 to 41.0.0 in /docs
#3673	ci,ascent: disable install tests
#3681	Fix: std::min w/ windows.h in C-Blosc2
#3657	Allow Span in files opened for Append
#3623	ci: use nvcc_wrapper in adiosKokkos
#3619	Backports bp5 bugfix
#3605	Adding missing HIP specific functionality
#3607	Backport: Heat Transfer Example: MPI Datatype #3593
#3593	Heat Transfer Example: MPI Datatype
#3591	Implement BP5 (and BP4) reader-side memory selection, do testing

[vicentebolea]

@eisenhauer @pnorbert