py3: add b'' prefixes in tests/test-extension.t
We are now close to getting this test pass on Python 3.
# skip-blame because just b'' prefixes.
Differential Revision: https://phab.mercurial-scm.org/D2478
BasedOnStyle: LLVM
IndentWidth: 8
UseTab: ForIndentation
BreakBeforeBraces: Linux
AllowShortIfStatementsOnASingleLine: false
IndentCaseLabels: false
AllowShortBlocksOnASingleLine: false
AllowShortFunctionsOnASingleLine: false
IncludeCategories:
- Regex: '^<'
Priority: 1
- Regex: '^"'
Priority: 2