Bump tinymce-rails from 6.3.1 to 7.6.0

Bumps [tinymce-rails](https://github.com/spohlenz/tinymce-rails) from 6.3.1 to 7.6.0.
- [Release notes](https://github.com/spohlenz/tinymce-rails/releases)
- [Commits](spohlenz/tinymce-rails@v6.3.1...v7.6.0)

---
updated-dependencies:
- dependency-name: tinymce-rails
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <[email protected]>

Gemfile.lock

@@ -178,7 +178,7 @@ GEM
     em-websocket (0.5.3)
       eventmachine (>= 0.12.9)
       http_parser.rb (~> 0)
-    erubi (1.13.0)
+    erubi (1.13.1)
     erubis (2.7.0)
     ethon (0.16.0)
       ffi (>= 1.15.0)
@@ -269,7 +269,7 @@ GEM
       rb-fsevent (~> 0.10, >= 0.10.3)
       rb-inotify (~> 0.9, >= 0.9.10)
     logger (1.6.1)
-    loofah (2.23.1)
+    loofah (2.24.0)
       crass (~> 1.0.2)
       nokogiri (>= 1.12.0)
     lumberjack (1.2.8)
@@ -362,7 +362,7 @@ GEM
       rack (~> 2.2, >= 2.2.4)
     rack-proxy (0.7.7)
       rack
-    rack-test (2.1.0)
+    rack-test (2.2.0)
       rack (>= 1.3)
     rack-timeout (0.7.0)
     rails (6.1.7.2)
@@ -497,7 +497,7 @@ GEM
     tilt (2.0.11)
     timecop (0.9.10)
     timeout (0.4.3)
-    tinymce-rails (6.3.1)
+    tinymce-rails (7.6.0)
       railties (>= 3.1.1)
     typhoeus (1.4.1)
       ethon (>= 0.9.0)