Add support to Circle CI
Add support to Circle CI

- Filter Circle CI for stable channel
- Avoid to build when Circle CI PR
- Fix bad env name

Signed-off-by: Uilian Ries <d4bad57018205bdda203549c36d3feb0bfe416a7@gmail.com>

cstb/conan-package-tools,cstb/conan-package-tools,conan-io/conan-package-tools