Revert "generate-repology-metadata: attempt to fix github action error"

Nested quoting is valid in bash.

Change introduced in 9168e963fa340f3fb76e482c02e5eaa66080d850 breaks
script and causes excludes list not being read:

realpath: '"scripts/repology/generate-repology-metadata.sh"': No such file or directory
[
grep: ./excluded_packages.txt: No such file or directory
  {
    "name": "8086tiny",
    "version": "1.25",
    "description": "A PC XT-compatible emulator/virtual machine",
    "homepage": "https://github.com/adriancable/8086tiny",
    "depends": ["bash", "coreutils", "ncurses"],
    "srcurl": "c79ca2a34d.tar.gz",
    "maintainer": "Fredrik Fornwall @fornwall"
  }grep: ./excluded_packages.txt: No such file or directory

scripts/repology/generate-repology-metadata.sh

@@ -20,7 +20,7 @@
 
 set -e
 
-BASEDIR=$(dirname "$(realpath \"$0\")")
+BASEDIR=$(dirname "$(realpath "$0")")
 export TERMUX_ARCH=aarch64
 
 check_package() { # path