Update link to Font Awesome gallery (mmistakes#3599)

Author: jasonhemann

docs/_docs/05-configuration.md

@@ -900,7 +900,7 @@ Author links are all optional, include the ones you want visible under the `auth
 | Name | Description |
 | --- | --- |
 | **label** | Link label (e.g. `"Twitter"`) |
-| **icon** | [Font Awesome icon](https://fontawesome.com/icons?d=gallery) classes (e.g. `"fab fa-fw fa-twitter-square"`) |
+| **icon** | [Font Awesome icon](https://fontawesome.com/v5/search) classes (e.g. `"fab fa-fw fa-twitter-square"`) |
 | **url** | Link URL (e.g. `"https://twitter.com/mmistakes"`) |
 
 ```yaml
@@ -933,7 +933,7 @@ Footer links can be added under the `footer.links` array.
 | Name | Description |
 | --- | --- |
 | **label** | Link label (e.g. `"Twitter"`) |
-| **icon** | [Font Awesome icon](https://fontawesome.com/icons?d=gallery) classes (e.g. `"fab fa-fw fa-twitter-square"`) |
+| **icon** | [Font Awesome icon](https://fontawesome.com/v5/search) classes (e.g. `"fab fa-fw fa-twitter-square"`) |
 | **url** | Link URL (e.g. `"https://twitter.com/mmistakes"`) |
 
 ```yaml

docs/_docs/10-layouts.md

@@ -128,7 +128,7 @@ Auto-generated table of contents list for your posts and pages can be enabled by
 | ---------   | -------- | ----------- | ------- |
 | **toc**     | Optional | Show table of contents. (boolean) | `false` |
 | **toc_label** | Optional | Table of contents title. (string) | `toc_label` in UI Text data file. |
-| **toc_icon**  | Optional | Table of contents icon, displays before the title. (string) | [Font Awesome](https://fontawesome.com/icons?d=gallery&s=solid&m=free) <i class="fas fa-file-alt"></i> **file-alt** icon. Other FA icons can be used instead. |
+| **toc_icon**  | Optional | Table of contents icon, displays before the title. (string) | [Font Awesome](https://fontawesome.com/v5/search?s=solid&m=free) <i class="fas fa-file-alt"></i> **file-alt** icon. Other FA icons can be used instead. |
 | **toc_sticky** | Optional | Stick table of contents to top of screen.                   | `false` |
 
 **TOC example with custom title and icon**
@@ -593,7 +593,7 @@ defaults:
 **Note:** To disable the author sidebar profile for a specific post or page, add `author_profile: false` to the YAML Front Matter instead.
 {: .notice--warning}
 
-To assign more author links, add to the `author.links` array  in [`_config.yml`]({{ "/docs/configuration/" | relative_url }}) link so. Any of [Font Awesome's icons](https://fontawesome.com/icons?d=gallery) are available for use.
+To assign more author links, add to the `author.links` array  in [`_config.yml`]({{ "/docs/configuration/" | relative_url }}) link so. Any of [Font Awesome's icons](https://fontawesome.com/v5/search) are available for use.
 
 ```yaml
 author: