Fixing failing thread sanitizer (#2051)

.github/workflows/ubuntu22-threadsani.yml

@@ -1,4 +1,4 @@
-name: Ubuntu 20.04 CI (GCC 9) with Thread Sanitizer
+name: Ubuntu 22.04 CI (GCC 11) with Thread Sanitizer
 
 on: [push, pull_request]
 
@@ -7,7 +7,7 @@ jobs:
     if: >-
       ! contains(toJSON(github.event.commits.*.message), '[skip ci]') &&
       ! contains(toJSON(github.event.commits.*.message), '[skip github]')
-    runs-on: ubuntu-20.04
+    runs-on: ubuntu-22.04
     steps:
       - uses: actions/checkout@v3
       - uses: actions/cache@v3

doc/iterate_many.md

@@ -17,6 +17,9 @@ Contents
 
 - [Motivations](#motivations)
 - [How it works](#how-it-works)
+  - [Context](#context)
+  - [Design](#design)
+  - [Threads](#threads)
 - [Support](#support)
 - [API](#api)
 - [Use cases](#use-cases)