fix: skip non-class definition headers in make_datamodel_glue.py

[wdconinc]

Briefly, what does this PR introduce?

In recent versions of EDM4hep, deprecated data types are defined as aliases to the recommended new data type: e.g.

namespace edm4hep {
using MCRecoCaloParticleAssociation [[deprecated("use CaloHitMCParticleLink instead")]] =
    edm4hep::CaloHitMCParticleLink;
}

This leads to issues in the datamodel_glue.h header, which defines them as a class, e.g.

/opt/local/include/edm4hep/MCRecoCaloParticleAssociation.h:7:7: error: typedef redefinition with different types ('edm4hep::CaloHitMCParticleLink' vs 'edm4hep::MCRecoCaloParticleAssociation')
    7 | using MCRecoCaloParticleAssociation [[deprecated("use CaloHitMCParticleLink instead")]] =
      |       ^
/home/wdconinc/git/EICrecon/build/include/services/io/podio/datamodel_glue.h:326:11: note: previous definition is here
  326 |     class MCRecoCaloParticleAssociation;
      |           ^

This PR avoids listing using aliases in the datamodel_glue.h headers by only processing data type headers with an actual class definition.

What kind of change does this PR introduce?

• Bug fix (issue #__)
• New feature (support for EDM4hep-0.99)
• Documentation update
• Other: __

Please check if this PR fulfills the following:

• Tests for the changes have been added
• Documentation has been added / updated
• Changes have been communicated to collaborators

Does this PR introduce breaking changes? What changes might users need to make to their code?

No.

Does this PR change default behavior?

No.

[github-actions]

Capybara summary for PR 1706

• rec_dis_10x100_minQ2=0_craterlake
• rec_dis_10x100_minQ2=1000_craterlake_tracking_only
• rec_dis_18x275_minQ2=0_craterlake_18x275
• rec_dis_18x275_minQ2=1000_craterlake_18x275
• rec_dis_5x41_minQ2=0_craterlake_5x41
• rec_e_1GeV_20GeV_craterlake
• rec_pi_1GeV_20GeV_craterlake
  ^{_{Last updated 2025-01-15T13:44-05:00 522a9a0}}

[simonge]

Looks good, I can't see any meaningful differences. As long as no one makes aliases between data types where the name of contains the string "class"