@aristoHero Yes, it seems the only way to work around this is to install the ca-certificates package. The main reason this is out of date in the first place is that the image is about 2.5 years old now.
I would have suggested to use HOMEBREW_NO_AUTO_UPDATE=1 brew install ca-certificates to cut down on the install time due to home-brew updating itself, but the ca-certificates package was not introduced to Homebrew until late 2021: ca-certificates 2021-09-30 (new formula) · Homebrew/homebrew-core@ef2fb64 · GitHub
The image was built in September 2020 (Xcode 11.7 Released), therefore this formula is not present in the image until Homebrew gets updated.
I would definitely suggest, if you can, moving to a newer Xcode image. The 11.7 image will be deprecated and removed later in the year, so being ahead of the curve will be beneficial!