build: update flutter to 2.2.0

[wasabeef]

What does this change?

• Update to 2.2.0

[codecov]

Codecov Report

Merging #111 (47e3f33) into main (dde0c14) will decrease coverage by 0.35%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##             main     #111      +/-   ##
==========================================
- Coverage   98.22%   97.86%   -0.36%     
==========================================
  Files          18       18              
  Lines         563      563              
==========================================
- Hits          553      551       -2     
- Misses         10       12       +2     

Impacted Files	Coverage Δ
...e/lib/generators/integrations/svg_integration.dart	90.47% <0.00%> (-9.53%)	⬇️

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