Revert "Highlight julia-repl code in Markdown specially (#54423)"

This reverts commit 6582eaa.

Author: KristofferC

stdlib/Markdown/src/Markdown.jl

@@ -47,7 +47,6 @@ const MARKDOWN_FACES = [
     :markdown_h6 => Face(height=1.05, inherit=:markdown_header),
     :markdown_admonition => Face(weight=:bold),
     :markdown_code => Face(inherit=:code),
-    :markdown_julia_prompt => Face(inherit=:repl_prompt_julia),
     :markdown_footnote => Face(inherit=:bright_yellow),
     :markdown_hrule => Face(inherit=:shadow),
     :markdown_inlinecode => Face(inherit=:markdown_code),

stdlib/Markdown/src/render/terminal/render.jl

@@ -118,21 +118,6 @@ end
 function term(io::IO, md::Code, columns)
     code = if md.language == "julia"
         highlight(md.code)
-    elseif md.language == "julia-repl" || Base.startswith(md.language, "jldoctest")
-        hl = AnnotatedString(md.code)
-        for (; match) in eachmatch(r"(?:^|\n)julia>", hl)
-            StyledStrings.face!(match, :markdown_julia_prompt)
-            afterprompt = match.offset + ncodeunits(match) + 1
-            _, exprend = Meta.parse(md.code, afterprompt, raise = false)
-            highlight!(hl[afterprompt:prevind(md.code, exprend)])
-            if (nextspace = findnext(' ', md.code, exprend)) |> !isnothing
-                nextword = hl[exprend:prevind(hl, nextspace)]
-                if nextword == "ERROR:"
-                    StyledStrings.face!(nextword, :error)
-                end
-            end
-        end
-        hl
     elseif md.language == "styled"
         styled(md.code)
     else