Update the cv_bridge header files from .h to .hpp

[vamsikalagaturu]

Describe the bug

• The PR modifies the cv_bridge header files from .hpp to .h.
• However, the latest changes in cv_bridge repo suggests that the .h files are being deprecated in latest ROS 2 versions (PR).

Fix

• Revert back to .hpp as default header files for cv_bridge or support both .h and .hpp files

• Version used (branch/commit):
  • OS: Ubuntu 22.04
  • ROS version: Rolling/Iron