Reduce MSRV to 1.88

Seems to build OK

Author: sourcefrog

.github/workflows/ci.yml

@@ -48,7 +48,7 @@ jobs:
         uses: actions/checkout@v6
 
       - name: Install Rust toolchain
-        uses: dtolnay/rust-toolchain@1.90.0
+        uses: dtolnay/rust-toolchain@1.88.0
 
       - name: Check
         run: cargo check

Cargo.toml

@@ -9,7 +9,7 @@ repository = "https://github.com/prefix-dev/flickzeug"
 readme = "README.md"
 keywords = ["diff", "patch", "merge"]
 categories = ["text-processing"]
-rust-version = "1.89.0"
+rust-version = "1.88"
 edition = "2024"
 
 [dependencies]