Update flash examples in README

[edenlightning]

What does this PR do?

Fixes # (issue)

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• Did you write any new necessary tests? [not needed for typos/docs]
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[codecov]

Codecov Report

Merging #91 (a945331) into master (5aecfad) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master      #91   +/-   ##
=======================================
  Coverage   86.63%   86.63%           
=======================================
  Files          45       45           
  Lines        1369     1369           
=======================================
  Hits         1186     1186           
  Misses        183      183           

Flag	Coverage Δ
unittests	86.63% <ø> (ø)

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