refactor(docs-infra): remove unused `_edit-page-cta.scss` file (#40704)

This commit removes the `_edit-page-cta.scss` file, which is no longer
used (i.e. the rules it contains do not match any element in the app).

PR Close #40704

aio/src/styles/2-modules/_edit-page-cta.scss

@@ -1,10 +0,0 @@
-.edit-page-cta {
-    font-weight: 400;
-    @include font-size(14);
-    color: $blue;
-    text-align: right;
-    margin-right: 32px;
-    display: block;
-    position: absolute;
-    right: 0;
-}

aio/src/styles/2-modules/_modules-dir.scss

@@ -14,7 +14,6 @@
    @import 'contributor';
    @import 'deploy-theme';
    @import 'details';
-   @import 'edit-page-cta';
    @import 'errors';
    @import 'features';
    @import 'filetree';