Log Message:
Update to 0.3.4

Upstream changes:
rlang 0.3.4

    Fixed a unit test that failed on the Solaris CRAN machine.

rlang 0.3.3

    Fixed an issue in knitr that caused backtraces to print even when error = TRUE.

    maybe_missing() gains a default argument.

rlang 0.3.2

    Fixed protection issue reported by rchk.

    The experimental option rlang__backtrace_on_error is no longer experimental \ 
and has been renamed to rlang_backtrace_on_error.

    New “none” option for rlang_backtrace_on_error.

    Unary operators applied to quosures now give better error messages.

    Fixed issue with backtraces of warnings promoted to error, and entraced via \ 
withCallingHandlers(). The issue didn’t affect entracing via top level \ 
options(error = rlang::entrace) handling.