Fix clippy and azure pipelines

azure-pipelines.yml

@@ -22,6 +22,7 @@ jobs:
       "C:\Program Files\Git\mingw64\bin\curl.exe" -sSf -o rustup-init.exe https://win.rustup.rs/
       .\rustup-init.exe -y
       set PATH=%PATH%;%USERPROFILE%\.cargo\bin
+      rustup update
       rustc -V
       cargo -V
     displayName: 'Installing Rust'

vm/src/obj/objsequence.rs

@@ -218,6 +218,7 @@ pub fn get_item(
 
 type DynPyIter<'a> = Box<dyn ExactSizeIterator<Item = &'a PyObjectRef> + 'a>;
 
+#[allow(clippy::len_without_is_empty)]
 pub trait SimpleSeq {
     fn len(&self) -> usize;
     fn iter(&self) -> DynPyIter;