fix(katana): init interval block producer with updated block env

[kariy]

The issue was that the pending block (when using interval block producer) was being initialized with previous block environment, making the pending block to have the latest block number (block number of a block that has been canonicalized) when it should've had latest block number + 1.

Though this is an entirely separate issue from #1475, but they corrupt each other.

[codecov]

Codecov Report

Attention: 2 lines in your changes are missing coverage. Please review.

Comparison is base (7527fcd) 69.40% compared to head (9419571) 69.51%.

Files	Patch %	Lines
crates/katana/core/src/sequencer.rs	90.47%	2 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1477      +/-   ##
==========================================
+ Coverage   69.40%   69.51%   +0.11%     
==========================================
  Files         228      228              
  Lines       22138    22158      +20     
==========================================
+ Hits        15364    15403      +39     
+ Misses       6774     6755      -19     

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