Bump Microsoft.Extensions.Caching.Memory from 3.1.8 to 3.1.9 (#1912)
Bump Microsoft.Extensions.Caching.Memory from 3.1.8 to 3.1.9 (#1912)

Bumps [Microsoft.Extensions.Caching.Memory](https://github.com/aspnet/Extensions) from 3.1.8 to 3.1.9.
- [Release notes](https://github.com/aspnet/Extensions/releases)
- [Commits](https://github.com/aspnet/Extensions/compare/v3.1.8...v3.1.9)

Signed-off-by: dependabot[bot] <5bdcd3c0d4d24ae3e71b3b452a024c6324c7e4bb@github.com>

Co-authored-by: dependabot[bot] <1c358da00a777d4e9898c1280ab801e2df165188@users.noreply.github.com>
joemcbride/graphql-dotnet,graphql-dotnet/graphql-dotnet,joemcbride/graphql-dotnet,graphql-dotnet/graphql-dotnet,graphql-dotnet/graphql-dotnet