Increase MSRV to 1.88.0

Increase MSRV to 1.88.0 to match datafusion 51.

Author: mjgarton

.github/workflows/ci.yml

@@ -81,6 +81,6 @@ jobs:
     - uses: actions/checkout@v4
     - uses: actions-rs/toolchain@v1
       with:
-        toolchain: "1.86.0"
+        toolchain: "1.88.0"
         override: true
     - run: cargo build --all-features

Cargo.toml

@@ -5,7 +5,7 @@ members = ["datafusion-postgres", "datafusion-postgres-cli", "arrow-pg", "datafu
 [workspace.package]
 edition = "2021"
 license = "Apache-2.0"
-rust-version = "1.86.0"
+rust-version = "1.88.0"
 authors = ["Ning Sun <[email protected]>"]
 keywords = ["database", "postgresql", "datafusion"]
 homepage = "https://github.com/datafusion-contrib/datafusion-postgres/"