* fix(cmake): add required emscripten flags

Signed-off-by: Henry Schreiner <henryschreineriii@gmail.com>

* Update emscripten.yaml

* fix(cmake): add required emscripten flags to headers target

Signed-off-by: Henry Schreiner <henryschreineriii@gmail.com>

* fix(cmake): incorrect detection of Emscripten

Signed-off-by: Henry Schreiner <henryschreineriii@gmail.com>

* fix(cmake): allow pybind11::headers to be modified

Signed-off-by: Henry Schreiner <henryschreineriii@gmail.com>

* fix(cmake): hide a warning when building the tests standalone

Signed-off-by: Henry Schreiner <henryschreineriii@gmail.com>

* fix(cmake): use explicit variable for is config

Signed-off-by: Henry Schreiner <henryschreineriii@gmail.com>

* fix(cmake): go back to ALIAS target

Signed-off-by: Henry Schreiner <henryschreineriii@gmail.com>

* chore: reduce overall diff

Signed-off-by: Henry Schreiner <henryschreineriii@gmail.com>

* chore: reduce overall diff

Signed-off-by: Henry Schreiner <henryschreineriii@gmail.com>

* chore: shorten code a bit

Signed-off-by: Henry Schreiner <henryschreineriii@gmail.com>

---------

Signed-off-by: Henry Schreiner <henryschreineriii@gmail.com>