feat(doc-generator): fix generation examples for provider-vault

[haarchri]

Description of your changes

the page_title is different for provider-vault then to other providers
page_title: "Vault: vault_ad_secret_backend_library resource"
for that reason i added a small code path to make the example generation working

Fixes #

I have:

• Read and followed Crossplane's contribution process.
• Run make reviewable to ensure this PR is ready for review.
• Added backport release-x.y labels to auto-backport this PR if necessary.

How has this code been tested

see Draft PR:
upbound/provider-vault#4

replace github.com/upbound/upjet => github.com/haarchri/upjet v0.9.0-rc.0.0.20230726-fb8ce3c61376be3aa89d8516adc69ced18544e10

[haarchri]

tested with upbound/provider-aws

add to go.mod replace github.com/upbound/upjet => github.com/haarchri/upjet v0.9.0-rc.0.0.20230726-fb8ce3c61376be3aa89d8516adc69ced18544e10

rm -rf examples-generated folder 
make generate
[...]
ls -ali | grep "examples-generated"
5406218 drwxr-x---@ 158 haarchri  staff   5056 Jul 31 13:53 examples-generated

git diff examples-generated is empty without changes

[ulucinar]

Thanks @haarchri, lgtm.