Add a search bar to link the original Pages to the searchable Pages (#6826)

* Add search bar to link the main page to the dynamic page

* Correct accidental description removal in Programming Playgrounds

* Remove erroneous space

Co-authored-by: David Ordás <3125580+davorpa@users.noreply.github.com>

* Add missing id to an input

* Update the link buttons with simpler text

Co-authored-by: Eric Hellman <eric@hellman.net>

* Remove trailing spaces on new websites paragraph

* Remove unnecesary trailing whitespaces

* Fix unclosed `<div>` wraping form and rollback those left aligned

Testing rendering via #6826

* Remove merge error

Co-authored-by: David Ordás <3125580+davorpa@users.noreply.github.com>
Co-authored-by: Eric Hellman <eric@hellman.net>

README.md

@@ -8,7 +8,15 @@
 
 </div>
 
-This page is available as an easy-to-read website at [![https://ebookfoundation.github.io/free-programming-books/](https://img.shields.io/website?style=flat&logo=www&logoColor=whitesmoke&label=https%3A%2F%2Febookfoundation.github.io&down_color=red&down_message=down&up_color=green&up_message=up&url=https%3A%2F%2Febookfoundation.github.io%2Ffree-programming-books%2F)](https://ebookfoundation.github.io/free-programming-books/)
+This page is available as an easy-to-read websites. Access them clicking on [![https://ebookfoundation.github.io/free-programming-books/](https://img.shields.io/website?style=flat&logo=www&logoColor=whitesmoke&label=Static%20site&down_color=red&down_message=down&up_color=green&up_message=up&url=https%3A%2F%2Febookfoundation.github.io%2Ffree-programming-books%2F)](https://ebookfoundation.github.io/free-programming-books/) or [![https://ebookfoundation.github.io/free-programming-books-search/](https://img.shields.io/website?style=flat&logo=www&logoColor=whitesmoke&label=Dynamic%20search%20site&down_color=red&down_message=down&up_color=green&up_message=up&url=https%3A%2F%2Febookfoundation.github.io%2Ffree-programming-books-search%2F)](https://ebookfoundation.github.io/free-programming-books-search/) links.
+
+<div align="center">
+  <form action="https://ebookfoundation.github.io/free-programming-books-search">
+    <input type="text" id="fpbSearch" name="search" placeholder="Search Book or Author"/>
+    <label for="submit"> </label>
+    <input type="submit" id="submit" name="submit" value="Search" />
+  </form>
+</div>
 
 
 ## Intro
@@ -48,6 +56,7 @@ Click on these badges to see how you might be able to help:
 
 </div>
 
+
 ## How to Share
 
 + [Share on Twitter](http://twitter.com/intent/tweet?text=https://github.com/EbookFoundation/free-programming-books%0AFree%20Programming%20Books)