v1.18: cli: skip no-op program buffer writes (backport of #277)

[mergify]

Problem

When retrying a program deploy, a buffer account might have already been partially written to but the cli program deployer will try to write the entire buffer again, wasting time and transactions.

Summary of Changes

• Before pushing a buffer write transaction, first check if the buffer data is already written with the desired data

Fixes #

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This is an automatic backport of pull request #277 done by [Mergify](https://mergify.com).

[codecov-commenter]

Codecov Report

Attention: Patch coverage is 22.22222% with 28 lines in your changes are missing coverage. Please review.

Project coverage is 81.6%. Comparing base (e9bc805) to head (0a4c7a8).

Additional details and impacted files

@@           Coverage Diff           @@
##            v1.18     #308   +/-   ##
=======================================
  Coverage    81.6%    81.6%           
=======================================
  Files         827      827           
  Lines      224517   224535   +18     
=======================================
+ Hits       183263   183331   +68     
+ Misses      41254    41204   -50     

[CriesofCarrots]

Approving for backport since this is a cli-only (low-risk) change