Update Example header in admonition to render PDF better, see #44866. (…

…#45026)

(cherry picked from commit d29d2d6)

base/floatfuncs.jl

@@ -97,9 +97,8 @@ julia> round(357.913; sigdigits=4, base=2)
     Rounding to specified digits in bases other than 2 can be inexact when
     operating on binary floating point numbers. For example, the [`Float64`](@ref)
     value represented by `1.15` is actually *less* than 1.15, yet will be
-    rounded to 1.2.
+    rounded to 1.2. For example:
 
-    # Examples
     ```jldoctest; setup = :(using Printf)
     julia> x = 1.15
     1.15