feat: add example value for blob.GasPrice

[jcstein]

Summary

Open RPC spec generation errors, due to a missing sample value for blob.GasPrice.

Problem

Missing sample value in api/docgen/examples.go.

Logs from running on v0.13.0:

--> Generating OpenRPC spec
failed to retrieve example value for type: blob.GasPrice on parent 'blob.GasPrice')
{
    "openrpc": "1.2.6",
    "info": {
        "title": "Celestia Node API",
        "description": "The Celestia Node API is the collection of RPC methods that can be used to interact with the services provided by Celestia Data Availability Nodes.",
        "version": "v0.11.0"
    },

Output from logs running on v0.11.0, as another check to see that this worked before:

--> Generating OpenRPC spec
{
    "openrpc": "1.2.6",
    "info": {
        "title": "Celestia Node API",
        "description": "The Celestia Node API is the collection of RPC methods that can be used to interact with the services provided by Celestia Data Availability Nodes.",
        "version": "v0.11.0"
    },

Solution

Add sample value.

Output after testing

Other issues found while testing

API version is still v0.11.0, which is the same as last few releases, i just ran make openrpc-gen on v0.11.0 and the API version is the same there. This is already, addressed in #2549, and I am highlighting to bring it out from stale state.

Proposed solutions for other issues found

To avoid this in the future, i would like to see if we can work this feature request to add openrpc.json on main into celestia-node, so that there is validation before publishing specs, and a history of past versions of the openrpc.json, stored on main with releases. otherwise we JTMB the person updating node-rpc-docs on almost 10000 lines of spec code

Note, this output must not contain the output which precedes the json:
--> Generating OpenRPC spec

[vgonkivs]

Thanks for taking care of it 🙏 🚀

[jcstein]

my pleasure, thanks for the reviews!