Configure clippy for dbg_macro and MSRV (#47)

* Add MSRV to clippy.toml

This is probably not as good as checking compilation with
the MSRV rustc. It can't check dependencies. But it will probably
prevent using new features in this repo.

* Enable clippy::dbg_macro to catch dbg! in release builds

.github/workflows/main.yml

@@ -22,6 +22,6 @@ jobs:
     - name: Build
       run: cargo build --release --verbose
     - name: Clippy
-      run: cargo clippy --all-targets -- -D warnings
+      run: cargo clippy --all-targets -- -D warnings -D clippy::dbg_macro
     - name: Run tests
       run: cargo test --verbose -- --skip sourcegen_ast --skip sourcegen_ast_nodes

clippy.toml

@@ -1,2 +1,4 @@
 # This does not work for some reason.
 # filter-map-identitiy = false
+
+msrv = "1.70.0"

crates/oq3_semantics/examples/semdemo.rs

@@ -91,6 +91,7 @@ fn main() {
             result.program().print_asg_debug();
         }
 
+        #[allow(clippy::dbg_macro)]
         Some(Commands::Semantic { file_name }) => {
             let result = syntax_to_semantics::parse_source_file(file_name);
             let have_errors = result.any_errors();

local_CI.sh

@@ -5,5 +5,5 @@
 
 cargo fmt --all -- --check || exit 1
 cargo build --release --verbose || exit 1
-cargo clippy --all-targets -- -D warnings || exit 1
+cargo clippy --all-targets -- -D warnings -D clippy::dbg_macro || exit 1
 cargo test --verbose -- --skip sourcegen_ast --skip sourcegen_ast_nodes || exit 1