chore: update msrv to 1.70.0

Author: MathiasPius

.github/workflows/CI.yml

@@ -80,15 +80,15 @@ jobs:
     - run: cargo hack check --feature-powerset --no-dev-deps
 
   check-msrv:
-    # Run `cargo check` on our minimum supported Rust version (1.60.0). This
+    # Run `cargo check` on our minimum supported Rust version (1.70.0). This
     # checks with minimal versions; maximal versions are checked above.
     name: "cargo check (+MSRV -Zminimal-versions)"
     needs: check
     runs-on: ubuntu-latest
     strategy:
       matrix:
         toolchain:
-        - 1.65.0
+        - 1.70.0
         - stable
     steps:
     - uses: actions/checkout@v4

Cargo.toml

@@ -13,7 +13,7 @@ categories = [
 keywords = ["tracing", "opentelemetry", "jaeger", "zipkin", "async"]
 license = "MIT"
 edition = "2021"
-rust-version = "1.65.0"
+rust-version = "1.70.0"
 
 [features]
 default = ["tracing-log", "metrics"]