Include vendor extensions from security scheme

[jirikuncar]

Add missing vendor extensions from security scheme.

https://openapi-generator.slack.com/archives/CLSB0U0R5/p1576666747065600

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---

@wing328 (2015/07) ❤️
@jimschubert (2016/05) ❤️
@cbornet (2016/05)
@ackintosh (2018/02) ❤️
@jmini (2018/04) ❤️
@etherealjoy (2019/06)

[jimschubert]

Nice. Thanks for the fix!

[jirikuncar]

How is the CircleCI error related to this PR?

UNCOMMITTED CHANGES ERROR
There are uncommitted changes in working tree after execution of 'bin/ensure-up-to-date'
Perform git diff
diff --git a/docs/generators/kotlin.md b/docs/generators/kotlin.md
index 86fbf23e5d..411a1bfad3 100644
--- a/docs/generators/kotlin.md
+++ b/docs/generators/kotlin.md
@@ -19,3 +19,4 @@ sidebar_label: kotlin
 |dateLibrary|Option. Date library to use|<dl><dt>**string**</dt><dd>String</dd><dt>**java8**</dt><dd>Java 8 native JSR310 (jvm only)</dd><dt>**threetenbp**</dt><dd>Threetenbp (jvm only)</dd><dl>|java8|
 |collectionType|Option. Collection type to use|<dl><dt>**array**</dt><dd>kotlin.Array</dd><dt>**list**</dt><dd>kotlin.collections.List</dd><dl>|array|
 |library|Library template (sub-template) to use|<dl><dt>**jvm-okhttp4**</dt><dd>[DEFAULT] Platform: Java Virtual Machine. HTTP client: OkHttp 4.2.0 (Android 5.0+ and Java 8+). JSON processing: Moshi 1.8.0.</dd><dt>**jvm-okhttp3**</dt><dd>Platform: Java Virtual Machine. HTTP client: OkHttp 3.12.4 (Android 2.3+ and Java 7+). JSON processing: Moshi 1.8.0.</dd><dt>**retrofit2**</dt><dd>Platform: Java Virtual Machine. HTTP client: Retrofit 2.6.2.</dd><dt>**multiplatform**</dt><dd>Platform: Kotlin multiplatform. HTTP client: Ktor 1.2.4. JSON processing: Kotlinx Serialization: 0.12.0.</dd><dl>|jvm-okhttp4|
+|requestDateConverter|JVM-Option. Defines in how to handle date-time objects that are used for a request (as query or parameter)|<dl><dt>**toJson**</dt><dd>Date formater option using a json converter.</dd><dt>**toString**</dt><dd>[DEFAULT] Use the 'toString'-method of the date-time object to retrieve the related string representation.</dd><dl>|toString|
Perform git status
On branch pull/4830
Changes not staged for commit:
  (use "git add <file>..." to update what will be committed)
  (use "git checkout -- <file>..." to discard changes in working directory)

	modified:   docs/generators/kotlin.md

no changes added to commit (use "git add" and/or "git commit -a")
Please run 'bin/utils/ensure-up-to-date' locally and commit changes (UNCOMMITTED CHANGES ERROR)

Exited with code exit status 1

[wing328]

It's not related to this PR and I've just pushed a fix to the master.

[wing328]

Thanks for the fix, which also looks good to me.