Delete Redundant Generators

[bear-is-asleep]

Description

The MultiPart and MultiVertex generators have been moved to larsim. Fixes SBNSoftware/sbndcode#835.

Dependent on LArSoft/larsim#162

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[justinjmueller]

We discussed this offline. Looks good to me!

[kjplows]

trigger build LArSoft/lar*@LARSOFT_SUITE_v10_12_02

[FNALbuild]

✔️ CI build for LArSoft Succeeded on slf7 for c14:prof -- details available through the CI dashboard

[FNALbuild]

✔️ CI build for LArSoft Succeeded on slf7 for e26:prof -- details available through the CI dashboard

[FNALbuild]

❌ CI build for SBND Failed at phase build SBND on slf7 for c14:prof -- details available through the CI dashboard

🚨 For more details about the failed phase, check the build SBND phase logs

parent CI build details are available through the CI dashboard

[FNALbuild]

❌ CI build for ICARUS Failed at phase build ICARUS on slf7 for c14:prof -- details available through the CI dashboard

🚨 For more details about the failed phase, check the build ICARUS phase logs

parent CI build details are available through the CI dashboard

[FNALbuild]

⚠️ CI build for SBND Warning at phase ci_tests SBND on slf7 for e26:prof - ignored warnings for build -- details available through the CI dashboard

🚨 For more details about the warning phase, check the ci_tests SBND phase logs

parent CI build details are available through the CI dashboard

[FNALbuild]

❌ CI build for ICARUS Failed at phase ci_tests ICARUS on slf7 for e26:prof - ignored warnings for build -- details available through the CI dashboard

🚨 For more details about the failed phase, check the ci_tests ICARUS phase logs

parent CI build details are available through the CI dashboard