Behavoiur of allOf in case of nested objects.

**What version of Ajv are you using? Does the issue happen if you use the latest version?**
"ajv": "^6.12.2",
"ajv-keywords": "^3.4.1"

**Ajv options object**

```javascript
schemaId: 'auto',
allErrors: true,
jsonPointers: true,
verbose: true,
$data: true
```

**JSON Schema**

```json
{
"type": "object",
"properties": {
"aciveIndex": {
"type": "number"
},
"basicInfo": {
"type": "object",
"properties": {
"firstName": {
"type": "string"
},
"lastName": {
"type": "string"
},
"gender": {
"type": "string",
"enum": ["Male", "Female", "Other"]
},
"yearOfBirth": {
"type": "number"
}
},
"required": [
"firstName",
"lastName",
"gender",
"yearOfBirth"
]
},
"educationInfo": {
"type": "object",
"properties": {
"testName": {
"type": "string",
"enum": [
"GRE",
"GMAT",
"None"
]
},
"testScore": {
"type": "number",
"minimum": 0,
"allOf":[{
"if": {
"const": "GRE"
},
"then":{
"maximum": 350
}
},{
"if": {
"const": "GMAT"
},
"then":{
"maximum": 800
}
}]
},
"yearOfExamination": {
"type": "number",
"minimum": 2015,
"maximum": 2021
},
"graduationInstitute": {
"type": "string"
},
"graduationFieldOfStudy": {
"type": "string"
},
"graduationGpa": {
"type": "number",
"miximum": 100
},
"graduationYearOfCompletion": {
"type": "number",
"maximum": 2021
}
},
"allOf": [
{
"required": [
"testName",
"graduationInstitute",
"graduationFieldOfStudy",
"graduationYearOfCompletion"
]
},
{
"if": {
"properties":{
"basicInfo": {
"properties":{
"yearOfBirth": {
"maximum": 2017
}
}
}
}
},
"then": {
"required": ["graduationGpa"]
}
},
{
"if": {
"properties":{
"testName": {
"const": "None"
}
}
},
"then":{
"required": []
},
"else": {
"required": [
"testScore",
"yearOfExamination"
]
}
}
]
},
"workInfo": {}
}
}
```

**Sample data**

```json
{
"basicInfo": {
"firstName": "shiv",
"lastName": "Garg",
"gender": "Male",
"yearOfBirth": 1994
},
"educationInfo": {
"testName": "GRE",
"graduationInstitute": "abc",
"graduationFieldOfStudy": "abc",
"graduationYearOfCompletion": 2016,
"testScore": 900,
"yearOfExamination": 2019
}
}
```

For the given schema mentioned here. I need to do two things.
1. If the `basicInfo.yearOfBirth` is less than `2017` then `educationInfo.graduationGpa` is required.
2. GRE scores should not be more than 350 and GMAT scores should not be more than 800.

I am not able to make these two conditions work. Especially I am more interested in knowing the behaviour of allOf and if condition inside allOf. Secondly when we are writing any if condition should we specify sub-properties only or properties from the root path.
(this is a part of very-very big schema which I have reduced for the sake of this issue)