Fix: sort L1 accepted_ops by L1 txid

[kantai]

This PR sorts accepted L1 operations by their txids so that ops_hash and consensus_hash are consistent between nodes. This also makes op ordering in the block_ops tables consistent.

It is necessary to sort by txid because the current version of the subnet codebase does not track a "vtxindex"-like field for the Stacks L1 operations.

[codecov[bot]]

Codecov Report

Merging #306 (f95f869) into master (d20406f) will not change coverage. The diff coverage is n/a.

@@           Coverage Diff           @@
##           master     #306   +/-   ##
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  Coverage   86.38%   86.38%           
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  Files           6        6           
  Lines         360      360           
  Branches       73       73           
=======================================
  Hits          311      311           
  Misses         49       49           

[blockstack-devops]

:tada: This PR is included in version 0.7.1 :tada:

The release is available on GitHub release

Your semantic-release bot :package::rocket:

[obycode]

Oops, we should've switched that to merge into develop. I'll change the default branch.