Need to run `pac solution pack` with -pca twice to include canvas app changes

[andersgMSFT]

When using pac solution pack with the processCanvasApp flag, it looks like changes to the canvas app source code are not included in the zipped solution unless you run the pac command twice.

I also noticed a difference in file size for the zip files, where the first run results in a smaller file than the following.

See below for examples of how I run the command and the resulting zip files:

PS C:\depot\powerAppsTest> pac solution pack -pca -z temp/zippedSolution.zip -f .\PowerPlatform\BcSampleAppsSolution\

Packing Solution...

Packing C:\depot\powerAppsTest\PowerPlatform\BcSampleAppsSolution to C:\depot\powerAppsTest\temp\zippedSolution.zip

Processing Component: Entities
Processing Component: Roles
Processing Component: Workflows
Processing Component: FieldSecurityProfiles
Processing Component: Templates
Processing Component: EntityMaps
Processing Component: EntityRelationships
Processing Component: OrganizationSettings
Processing Component: optionsets
Processing Component: CustomControls
Processing Component: EntityDataProviders
Processing Component: CanvasApps
 - new_bcwarehousehelper_290e3

-- packing Canvas app new_bcwarehousehelper_290e3...
Pack from C:\depot\powerAppsTest\PowerPlatform\BcSampleAppsSolution\CanvasApps\src\new_bcwarehousehelper_290e3 --> C:\depot\powerAppsTest\PowerPlatform\BcSampleAppsSolution\CanvasApps\new_bcwarehousehelper_290e3_DocumentUri.msapp
  source format version: 0.24

Unmanaged Pack complete.

Packed Solution.

PS C:\depot\powerAppsTest> pac solution pack -pca -z temp/zippedSolution2.zip -f .\PowerPlatform\BcSampleAppsSolution\

Packing Solution...

Packing C:\depot\powerAppsTest\PowerPlatform\BcSampleAppsSolution to C:\depot\powerAppsTest\temp\zippedSolution2.zip

Processing Component: Entities
Processing Component: Roles
Processing Component: Workflows
Processing Component: FieldSecurityProfiles
Processing Component: Templates
Processing Component: EntityMaps
Processing Component: EntityRelationships
Processing Component: OrganizationSettings
Processing Component: optionsets
Processing Component: CustomControls
Processing Component: EntityDataProviders
Processing Component: CanvasApps
 - new_bcwarehousehelper_290e3

-- packing Canvas app new_bcwarehousehelper_290e3...
Pack from C:\depot\powerAppsTest\PowerPlatform\BcSampleAppsSolution\CanvasApps\src\new_bcwarehousehelper_290e3 --> C:\depot\powerAppsTest\PowerPlatform\BcSampleAppsSolution\CanvasApps\new_bcwarehousehelper_290e3_DocumentUri.msapp
  source format version: 0.24

Unmanaged Pack complete.

Packed Solution.

[filcole]

Maybe related to #334