Trac #30979: Remove duplication of options handled in src/bin/sage and build/bin/sage-site

(from #30846)

We remove the duplication of lines like
{{{
if [ "$1" = '-optional' -o "$1" = "--optional" ]; then
    shift
    exec sage-list-packages optional $@
fi
}}}
in `src/bin/sage` and `build/bin/sage-site`.

We keep handling of the option `--installed` in `src/bin/sage` in
anticipation of #30940 (`src/bin/sage-list-packages`: Make it work if
`SAGE_ROOT` is not available).

URL: https://trac.sagemath.org/30979
Reported by: mkoeppe
Ticket author(s): Matthias Koeppe
Reviewer(s): Jonathan Kliem

Author: Release Manager

build/bin/sage-site

@@ -128,16 +128,6 @@ if [ "$1" = '-standard' -o "$1" = "--standard" ]; then
     exec sage-list-packages standard $@
 fi
 
-if [ "$1" = '-installed' -o "$1" = "--installed" ]; then
-    shift
-    exec sage-list-packages all --installed-only $@
-fi
-
-if [ "$1" = '-p' ]; then
-    echo "Error: Installing old-style SPKGs is no longer supported."
-    exit 1
-fi
-
 if [ "$1" = '-info' -o "$1" = '--info' ]; then
     shift
     for PKG in "$@"

src/bin/sage

@@ -979,27 +979,6 @@ install() {
     exit 0
 }
 
-
-if [ "$1" = '-package' -o "$1" = "--package" ]; then
-    shift
-    exec sage-package $@
-fi
-
-if [ "$1" = '-optional' -o "$1" = "--optional" ]; then
-    shift
-    exec sage-list-packages optional $@
-fi
-
-if [ "$1" = '-experimental' -o "$1" = "--experimental" ]; then
-    shift
-    exec sage-list-packages experimental $@
-fi
-
-if [ "$1" = '-standard' -o "$1" = "--standard" ]; then
-    shift
-    exec sage-list-packages standard $@
-fi
-
 if [ "$1" = '-installed' -o "$1" = "--installed" ]; then
     shift
     exec sage-list-packages all --installed-only $@
@@ -1014,15 +993,6 @@ if [ "$1" = '-p' ]; then
     install "$@"
 fi
 
-if [ "$1" = '-info' -o "$1" = '--info' ]; then
-    shift
-    for PKG in "$@"
-    do
-        sage-spkg --info "$PKG" || exit $?
-    done
-    exit 0
-fi
-
 if [ "$1" = '-sdist' -o "$1" = "--sdist" ]; then
     maybe_sage_location
     shift