irmin-cli: change --store irf to --store fs

[wyn]

The information in the Irmin website uses "fs" where-as the irmin-cli Resolver uses "irf". Changed command line and module sig to use fs and also updated cram tests.

NOTE previous use of "irf" will now error, I wasn't sure whether backwards compatibility was expected?

As an example, looking at the cli --help segment:

before

       -s VAL, --store=VAL
           The storage backend (one of git, git-mem, irf, mem, mem-http,
           git-http, pack or tezos). Default is `git'.

after

       -s VAL, --store=VAL
           The storage backend (one of git, git-mem, fs, mem, mem-http,
           git-http, pack or tezos). Default is `git'.

[wyn]

This looks great. Backwards compatibility is fine to break for this usage, especially since it was wrong wrt the docs. 🙈

Can you also put an entry in CHANGES.md mentioning the fix? (just insert a new ## Unreleased section at the top and follow the pattern of previous entries)

Thanks!

no probs, just force pushed that too.

Some context, I'm here on the mirageOS retreat and trying to learn more about Irmin so I thought I'd try some beginner bugs.

[codecov-commenter]

Codecov Report

Merging #2243 (fc0b5be) into main (4c38a4b) will decrease coverage by 0.02%. The diff coverage is 16.66%.

:exclamation: Current head fc0b5be differs from pull request most recent head 6114435. Consider uploading reports for the commit 6114435 to get more accurate results

:mega: This organization is not using Codecov’s GitHub App Integration. We recommend you install it so Codecov can continue to function properly for your repositories. Learn more

@@            Coverage Diff             @@
##             main    #2243      +/-   ##
==========================================
- Coverage   67.93%   67.91%   -0.02%     
==========================================
  Files         136      136              
  Lines       16603    16605       +2     
==========================================
- Hits        11279    11278       -1     
- Misses       5324     5327       +3     

Impacted Files	Coverage Δ
src/irmin-pack/unix/gc.ml	69.79% <0.00%> (-3.62%)	:arrow_down:
src/irmin-cli/resolver.ml	53.64% <50.00%> (ø)

... and 1 file with indirect coverage changes

:mega: We’re building smart automated test selection to slash your CI/CD build times. Learn more

[metanivek]

Some context, I'm here on the mirageOS retreat and trying to learn more about Irmin so I thought I'd try some beginner bugs.

Awesome -- enjoy the retreat! :camel:

[metanivek]

Thanks!