fix(p2p): set gossipsub buffersize to avoid missed blocks

[srene]

PR Standards

Opening a pull request should be able to meet the following requirements

--

PR naming convention: https://hackmd.io/@nZpxHZ0CT7O5ngTp0TP9mg/HJP_jrm7A

---

Close #972

<-- Briefly describe the content of this pull request -->

There is a channel in gossipsub implementation, used to consume packets received, that its default size is 32.
If the occupancy goes over the limit, packets are not added and dropped.
By setting a bigger buffer size for the channel we limit the problem, which was happening in cases where out of sync full-nodes where trying to apply long list of blocks, while receiving them from p2p at fast rate.

For Author:

• Targeted PR against correct branch
• included the correct type prefix in the PR title
• Linked to Github issue with discussion and accepted design
• Targets only one github issue
• Wrote unit and integration tests
• All CI checks have passed
• Added relevant godoc comments

---

For Reviewer:

• confirmed the correct type prefix in the PR title
• Reviewers assigned
• confirmed all author checklist items have been addressed

---

After reviewer approval:

• In case targets main branch, PR should be squashed and merged.
• In case PR targets a release branch, PR should be rebased.