In multiple places in the specs we have properties defined using the type number:

my_app_port:
type: number

Number is not a valid type for a property and the type should be replaced by integer or float.

my_app_port:
type: integer

Reminder: below are the valid types as defined in the spec:

Valid aliases Type URI
string tag:yaml.org,2002:str (default)
integer tag:yaml.org,2002:int
float tag:yaml.org,2002:float
boolean tag:yaml.org,2002:bool (i.e., a value either ‘true’ or ‘false’)
timestamp tag:yaml.org,2002:timestamp
null tag:yaml.org,2002:null