Adds copy buttons to API and field type sections (#2518)

Signed-off-by: Fanit Kolchina <kolchfa@amazon.com>

_api-reference/script-apis/exec-script.md

@@ -40,6 +40,7 @@ GET /_scripts/painless/_execute
   }
 }
 ```
+{% include copy-curl.html %}
 
 #### Sample response
 
@@ -94,6 +95,7 @@ PUT /testindex1
   }
 }
 ```
+{% include copy-curl.html %}
 
 Run a script to determine if a student is eligible to graduate with honors:
 
@@ -116,6 +118,7 @@ POST /_scripts/painless/_execute
   }
 }
 ```
+{% include copy-curl.html %}
 
 The response contains the result:
 
@@ -151,6 +154,7 @@ PUT /testindex1
   }
 }
 ```
+{% include copy-curl.html %}
 
 Run a script that converts a GPA on a 4.0 scale into a different scale that is provided as a parameter:
 
@@ -172,6 +176,7 @@ POST /_scripts/painless/_execute
   }
 }
 ```
+{% include copy-curl.html %}
 
 The response contains the result: