Add PRQL to README (#863)

Author: vanillajonathan

README.md

@@ -53,7 +53,7 @@ translators for Pygments lexers and styles.
 |   M    | Makefile, Mako, markdown, Mason, Mathematica, Matlab, mcfunction, Meson, Metal, MiniZinc, MLIR, Modula-2, MonkeyC, MorrowindScript, Myghty, MySQL                                                                                    |
 |   N    | NASM, Natural, Newspeak, Nginx configuration file, Nim, Nix                                                                                                                                                                          |
 |   O    | Objective-C, OCaml, Octave, Odin, OnesEnterprise, OpenEdge ABL, OpenSCAD, Org Mode                                                                                                                                                   |
-|   P    | PacmanConf, Perl, PHP, PHTML, Pig, PkgConfig, PL/pgSQL, plaintext, Plutus Core, Pony, PostgreSQL SQL dialect, PostScript, POVRay, PowerQuery, PowerShell, Prolog, PromQL, properties, Protocol Buffer, PSL, Puppet, Python, Python 2 |
+|   P    | PacmanConf, Perl, PHP, PHTML, Pig, PkgConfig, PL/pgSQL, plaintext, Plutus Core, Pony, PostgreSQL SQL dialect, PostScript, POVRay, PowerQuery, PowerShell, Prolog, PromQL, properties, Protocol Buffer, PRQL, PSL, Puppet, Python, Python 2 |
 |   Q    | QBasic, QML                                                                                                                                                                                                                          |
 |   R    | R, Racket, Ragel, Raku, react, ReasonML, reg, reStructuredText, Rexx, Ruby, Rust                                                                                                                                                     |
 |   S    | SAS, Sass, Scala, Scheme, Scilab, SCSS, Sed, Sieve, Smali, Smalltalk, Smarty, Snobol, Solidity, SourcePawn, SPARQL, SQL, SquidConf, Standard ML, stas, Stylus, Svelte, Swift, SYSTEMD, systemverilog                                 |