[0.2] Pin syn for yet another MSRV breakage

[TheBlueMatt]

No description provided.

[ldk-reviews-bot]

I've assigned @wpaulino as a reviewer!
I'll wait for their review and will help manage the review process.
Once they submit their review, I'll check if a second reviewer would be helpful.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 88.80%. Comparing base (58402ed) to head (12c52c7).
⚠️ Report is 2 commits behind head on 0.2.

Additional details and impacted files

@@            Coverage Diff             @@
##              0.2    #4177      +/-   ##
==========================================
+ Coverage   88.77%   88.80%   +0.03%     
==========================================
  Files         180      180              
  Lines      136626   136626              
  Branches   136626   136626              
==========================================
+ Hits       121288   121332      +44     
+ Misses      12531    12497      -34     
+ Partials     2807     2797      -10     

Flag	Coverage Δ
fuzzing	21.64% <ø> (ø)
tests	88.64% <ø> (+0.03%)	⬆️

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[tankyleo]

Sounds like we also need to do this for the downstream no-std crate build, and the msrv-no-dev-deps-check... this below passes on my machine on 1.63

diff --git a/ci/ci-tests.sh b/ci/ci-tests.sh
index c21c1e0e7..a0b54465a 100755
--- a/ci/ci-tests.sh
+++ b/ci/ci-tests.sh
@@ -124,6 +124,7 @@ cargo test -p lightning-invoice --verbose --color always --no-default-features -
 echo -e "\n\nTesting no_std build on a downstream no-std crate"
 # check no-std compatibility across dependencies
 pushd no-std-check
+[ "$RUSTC_MINOR_VERSION" -lt 68 ] && cargo update -p syn --precise "2.0.106" --verbose
 cargo check --verbose --color always
 [ "$CI_MINIMIZE_DISK_USAGE" != "" ] && cargo clean
 popd
@@ -131,6 +132,7 @@ popd
 # Test that we can build downstream code with only the "release pins".
 pushd msrv-no-dev-deps-check
 PIN_RELEASE_DEPS
+[ "$RUSTC_MINOR_VERSION" -lt 68 ] && cargo update -p syn --precise "2.0.106" --verbose
 cargo check
 [ "$CI_MINIMIZE_DISK_USAGE" != "" ] && cargo clean
 popd

[TheBlueMatt]

Grr, thanks.

[tankyleo]

CI failures seem unrelated

[tankyleo]

Making sure the --verbose delete here was intentional ?

[TheBlueMatt]

Yea, seemed useless.