modify comp. tool content type heading strings

[kbhawkey]

When the capture shortcode and templates are removed from website/content/en/docs/reference,
replace the corresponding code in the component tool generation code.

Example headings:

## {{% heading "synopsis" %}}
## {{% heading "examples" %}}
## {{% heading "options" %}}
## {{% heading "parentoptions" %}}
## {{% heading "seealso" %}}

Example front matter:

content_type: tool-reference

[kbhawkey]

/assign

[kbhawkey]

For more information, see PR kubernetes/website#21359

[kbhawkey]

/close

[k8s-ci-robot]

@kbhawkey: Closing this issue.

In response to this:

/close

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