[BUG][Kotlin] Kotlin client variable name

[andrewemery]

Description

Kotlin client generates invalid variable names for reserved words.

openapi-generator version

Working in: 4.1.2
Broken in: 4.1.3-SNAPSHOT

OpenAPI declaration file content or url

responses:
  '200':
    schema:
      properties:
        data: # kotlin reserved word
          type: string

Expected:

val `data`: String

Actual:

val ``data`` String

Command line used for generation

openapi-generator generate -g kotlin

Related issues/PRs

#3899

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[wing328]

Closed via #3993