Rollup merge of #82977 - camsteffen:opt-get-insert-def, r=m-ou-se

Rename `Option::get_or_default` to `get_or_insert_default`

...as [suggested](https://github.com/rust-lang/rust/issues/82901#issuecomment-793548515) by `@m-ou-se.` In hindsight this seems rather obvious, at least to me.

r? `@joshtriplett`

compiler/rustc_mir/src/lib.rs

@@ -25,7 +25,7 @@ Rust MIR: a lowered representation of Rust.
 #![feature(stmt_expr_attributes)]
 #![feature(trait_alias)]
 #![feature(option_expect_none)]
-#![feature(option_get_or_default)]
+#![feature(option_get_or_insert_default)]
 #![feature(or_patterns)]
 #![feature(once_cell)]
 #![feature(control_flow_enum)]

compiler/rustc_mir/src/transform/coverage/graph.rs

@@ -392,7 +392,8 @@ impl BasicCoverageBlockData {
             }
         }
         let operand = counter_kind.as_operand_id();
-        if let Some(replaced) = self.edge_from_bcbs.get_or_default().insert(from_bcb, counter_kind)
+        if let Some(replaced) =
+            self.edge_from_bcbs.get_or_insert_default().insert(from_bcb, counter_kind)
         {
             Error::from_string(format!(
                 "attempt to set an edge counter more than once; from_bcb: \