Sample configuration for Sitecore 10.1 using IAR. Adds an additional location that is later included by default in 10.2.

IAR.101.config

<?xml version="1.0" encoding="utf-8" ?>
<!--
Purpose: Adds in an additional location to load IAR files from
This config can be removed if the project is upgraded to 10.2+ since the path is set ootb
-->
<configuration xmlns:patch="http://www.sitecore.net/xmlconfig/" xmlns:role="http://www.sitecore.net/xmlconfig/role/">
  <sitecore>
    <databases>
      <database id="master" role:require="Standalone or ContentManagement">
        <dataProviders>
          <dataProvider>
            <param desc="readOnlyDataProviders">
              <protobufItems>
                <filePaths>
                  <filePath name="modules">/sitecore modules/items/$(id)</filePath>
                </filePaths>
              </protobufItems>
            </param>
          </dataProvider>
        </dataProviders>
      </database>
      <database id="core" role:require="Standalone or ContentManagement">
        <dataProviders>
          <dataProvider>
            <param desc="readOnlyDataProviders">
              <protobufItems>
                <filePaths>
                  <filePath name="modules">/sitecore modules/items/$(id)</filePath>
                </filePaths>
              </protobufItems>
            </param>
          </dataProvider>
        </dataProviders>
      </database>
      <database id="web">
        <dataProviders>
          <dataProvider>
            <param desc="readOnlyDataProviders">
              <protobufItems>
                <filePaths>
                  <filePath name="modules">/sitecore modules/items/$(id)</filePath>
                </filePaths>
              </protobufItems>
            </param>
          </dataProvider>
        </dataProviders>
      </database>
    </databases>
  </sitecore>
</configuration>