docs: update readme after website release

[incendial]

What is the purpose of this pull request? (put an "X" next to an item)

[X] Documentation update
[ ] Bug fix
[ ] New rule
[ ] Changes an existing rule
[ ] Add autofixing to a rule
[ ] Add a CLI option
[ ] Add something to the core
[ ] Other, please explain:

[codecov-commenter]

Codecov Report

Merging #415 (6c34432) into master (bc56884) will increase coverage by 0.25%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master     #415      +/-   ##
==========================================
+ Coverage   81.04%   81.29%   +0.25%     
==========================================
  Files         166      176      +10     
  Lines        3766     3833      +67     
==========================================
+ Hits         3052     3116      +64     
- Misses        714      717       +3     

Impacted Files	Coverage Δ
...c/analyzers/lint_analyzer/rules/rules_factory.dart	90.00% <0.00%> (-5.75%)	⬇️
.../src/analyzers/lint_analyzer/rules/rule_utils.dart	100.00% <0.00%> (ø)
...src/analyzers/lint_analyzer/rules/models/rule.dart	100.00% <0.00%> (ø)
.../analyzers/lint_analyzer/metrics/metric_utils.dart	100.00% <0.00%> (ø)
...ers/lint_analyzer/anti_patterns/pattern_utils.dart	100.00% <0.00%> (ø)
...s_list/member_ordering_extended/config_parser.dart	100.00% <0.00%> (ø)
...widget_per_file/prefer_single_widget_per_file.dart	100.00% <0.00%> (ø)
...nalyzers/lint_analyzer/rules/models/intl_rule.dart	100.00% <0.00%> (ø)
...yzers/lint_analyzer/rules/models/angular_rule.dart	100.00% <0.00%> (ø)
...les/rules_list/prefer_match_file_name/visitor.dart	100.00% <0.00%> (ø)
... and 6 more

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