Revert "feat(agnoster): add `anaconda` env information (#12434)"

This reverts commit 309129f651eeeca62c3a3b7f6817f0ac601db9f0.

themes/agnoster.zsh-theme

@@ -227,14 +227,6 @@ prompt_virtualenv() {
   fi
 }
 
-# Conda Virtualenv
-prompt_conda_virtualenv() {
-  if [[ -n $CONDA_PROMPT_MODIFIER ]]; then
-    prompt_segment black default ${CONDA_PROMPT_MODIFIER:1:-2}
-  fi
-}
-
-
 # Status:
 # - was there an error
 # - am I root
@@ -274,7 +266,6 @@ build_prompt() {
   prompt_bzr
   prompt_hg
   prompt_end
-  prompt_conda_virtualenv
 }
 
 PROMPT='%{%f%b%k%}$(build_prompt) '