feat: add default pygment themes friendly (light) and monokai (dark)

Author: jorgepiloto

src/ansys_sphinx_theme/theme/ansys_sphinx_theme/static/css/ansys_sphinx_theme.css

@@ -526,45 +526,6 @@ a > code.download {
   font-weight: normal;
 }
 
-/*
-#####################
-Sphinx gallery output
-#####################
-*/
-.sphx-glr-script-out .highlight pre {
-  background-color: var(--pst-color-codecell) !important;
-  color: var(--pst-color-codeout);
-}
-
-.prev-next-area a p.prev-next-title {
-  color: var(--pst-color-link);
-  font-weight: 600;
-  font-size: 1.1em;
-}
-
-.highlight .s1,
-.s2,
-.kc {
-  color: var(--pst-color-code-s1) !important;
-}
-
-html[data-theme="dark"] .highlight .kn {
-  color: #e18fff;
-  font-weight: normal;
-}
-
-.highlight .c1 {
-  color: var(--pst-color-code-c1);
-}
-
-html[data-theme="dark"] .highlight .n {
-  color: #b3d7ff;
-}
-
-html[data-theme="dark"] .highlight .nn {
-  color: #43d69d;
-  text-decoration: none;
-}
 /*
 ###############
 Dropdown button

src/ansys_sphinx_theme/theme/ansys_sphinx_theme/theme.conf

@@ -1,6 +1,5 @@
 [theme]
 inherit = pydata_sphinx_theme
-pygments_style = friendly
 
 [options]
 contact_mail =
@@ -15,3 +14,5 @@ switcher =
 use_meilisearch =
 article_header_start = breadcrumbs.html
 footer_end = theme-version.html
+pygment_light_style = friendly
+pygment_dark_style = monokai