GraphQL (Docs): Document the /admin/schema/validate endpoint

[aaroncarey]

Added documentation for the schema validation endpoint, per #6250 and GRAPHQL-578.

Fixes GRAPHQL-780

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[abhimanyusinghgaur]

Suggested some minor wording changes and a few spelling mistakes.
after those are addressed.

Reviewable status: 0 of 1 files reviewed, 4 unresolved discussions (waiting on @aaroncarey, @abhimanyusinghgaur, @bucanero, @danielmai, and @MichaelJCompton)

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wiki/content/graphql/admin/index.md, line 348 at r1 (raw file):

defnition 

definition

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wiki/content/graphql/admin/index.md, line 349 at r1 (raw file):

Quoted 4 lines of code…

You can validate a GraphQL schema before adding it to your database by sending
your schema defnition to the `/admin/schema/validate` endpoint, as in the
following HTTP request example:
Request header:

ssh > path: /admin/schema/validate > method: POST > content-type: application/json > ``` > Request body: > ``` Should we phrase it like this: ``` You can validate a GraphQL schema before adding it to your database by sending your schema definition in an HTTP POST request to the `/admin/schema/validate` endpoint, with the following body:

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*[wiki/content/graphql/admin/index.md, line 356 at r1](https://reviewable.io/reviews/dgraph-io/dgraph/6814#-MKsHv9l7raSs4q7O4ct:-MKsHv9l7raSs4q7O4cu:b-xhq5wc) ([raw file](https://github.com/dgraph-io/dgraph/blob/a179e80d05cb1fac6e0c0e854f74cc2e7ac56951/wiki/content/graphql/admin/index.md#L356)):*
> ```
> content-type: application/json
> ```
This header is not required in the HTTP request. The input is just plain text.
The HTTP response is JSON.
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*[wiki/content/graphql/admin/index.md, line 368 at r1](https://reviewable.io/reviews/dgraph-io/dgraph/6814#-MKsIm-D9PH_Vi3kk-5S:-MKsIm-D9PH_Vi3kk-5T:b-k00oht) ([raw file](https://github.com/dgraph-io/dgraph/blob/a179e80d05cb1fac6e0c0e854f74cc2e7ac56951/wiki/content/graphql/admin/index.md#L368)):*
> ```
> and
> ```
an


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[abhimanyusinghgaur]

Reviewable status: 0 of 1 files reviewed, 4 unresolved discussions (waiting on @aaroncarey, @abhimanyusinghgaur, @bucanero, @danielmai, and @MichaelJCompton)

[aaroncarey]

Reviewable status: 0 of 1 files reviewed, 4 unresolved discussions (waiting on @abhimanyusinghgaur, @bucanero, @danielmai, and @MichaelJCompton)

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wiki/content/graphql/admin/index.md, line 348 at r1 (raw file):

Previously, abhimanyusinghgaur (Abhimanyu Singh Gaur) wrote…

defnition 

definition

Done. Sorry that I missed that!

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wiki/content/graphql/admin/index.md, line 349 at r1 (raw file):

Previously, abhimanyusinghgaur (Abhimanyu Singh Gaur) wrote…

You can validate a GraphQL schema before adding it to your database by sending
your schema defnition to the `/admin/schema/validate` endpoint, as in the
following HTTP request example:
Request header:
```ssh
path: /admin/schema/validate
method: POST
content-type: application/json

Request body:

Should we phrase it like this:

You can validate a GraphQL schema before adding it to your database by sending
your schema definition in an HTTP POST request to the `/admin/schema/validate` endpoint, with the following body:

Thanks for this suggestion! I picked up some of this phrasing, but I wanted to retain the word "example" and also provide the example header that includes the content-type, as including that in the sentence made it too long.

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wiki/content/graphql/admin/index.md, line 356 at r1 (raw file):

Previously, abhimanyusinghgaur (Abhimanyu Singh Gaur) wrote…

content-type: application/json

This header is not required in the HTTP request. The input is just plain text.
The HTTP response is JSON.

Thanks for the clarification! Fixed.

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wiki/content/graphql/admin/index.md, line 368 at r1 (raw file):

Previously, abhimanyusinghgaur (Abhimanyu Singh Gaur) wrote…

and

an

Done.

[bucanero]

if you want, we could also add a curl example, like:

curl -X POST localhost:8080/admin/schema/validate --data-binary '@schema.graphql'

[bucanero]

LGTM

[aaroncarey]

Thanks!

Reviewable status: 0 of 1 files reviewed, 5 unresolved discussions (waiting on @aaroncarey, @abhimanyusinghgaur, @danielmai, and @MichaelJCompton)