text: Title: IntStr GetValueFromIntOrPercent assumes all strings are percentages
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  **What happened**:
  
  Using [GetValueFromIntOrPercent](https://github.com/kubernetes/apimachinery/blob/c76d55892ea23f279bd999f01f951e78434b6095/pkg/util/intstr/intstr.go#L154-L170) from the `intstr` package in `k8s.io/apimachinery/pkg/util/intstr`, I found there's a difference in behaviour between `{"foo": 1}` and `{"foo": "1"}`, but there is no difference in behaviour between `{"foo": "1"}` and `{"foo": "1%"}`
  
  When unmarshalling from JSON, {"foo": "1"} results in the intstr being of type String, this causes the [getIntOrPercentValue](https://github.com/kubernetes/apimachinery/blob/c76d55892ea23f279bd999f01f951e78434b6095/pkg/util/intstr/intstr.go#L176-L183) method to assume that it is a percentage when it is not. So a value of `"1"` becomes identical in behaviour to a value of `"1%"`.
  
  **What you expected to happen**:
  
  A value of `1` and `"1"` should cause the same behaviour.
  The code should check for the existence of a `%` in the string before determining it is a percentage
  
  **How to reproduce it (as minimally and precisely as possible)**:
  
  ```
  package main
  
  import (
  	"fmt"
  	"k8s.io/apimachinery/pkg/util/intstr"
  )
  
  func main() {
  	oneString := intstr.FromString("1")
  	val, err := intstr.GetValueFromIntOrPercent(&oneString, 10, false)
  	if err != nil {
  		panic(err)
  	}
  	fmt.Printf("(String) Expecting %d to equal 1\n", val)
  	
  	oneInt := intstr.FromInt(1)
  	val, err = intstr.GetValueFromIntOrPercent(&oneInt, 10, false)
  	if err != nil {
  		panic(err)
  	}
  	fmt.Printf("(Int) Expecting %d to equal 1\n", val)
  }
  ```
  
  Outputs:
  
  ```
  (String) Expecting 0 to equal 1
  (Int) Expecting 1 to equal 1
  ```
  
  https://play.golang.org/p/MR3M4UdWYph
  
  **Anything else we need to know?**:
  
  This was raised in [slack](https://kubernetes.slack.com/archives/C0EG7JC6T/p1583949884224600), @liggitt responded and noted that at first glance, where this is used in tree, the types have [validation](https://github.com/kubernetes/kubernetes/blob/c369cf187ea765c0a2387f2b39abe6ed18c8e6a8/pkg/apis/apps/validation/validation.go#L384-L399) to check string values are valid percents before being accepted and that if we want to fix this, a proper sweep of current in-tree uses should be checked to make sure that updating the behaviour wouldn't break any current uses
  
  @liggitt Also suggested it might be worth checking out of tree uses as well to be good citizens and linked to https://grep.app/search?q=.GetValueFromIntOrPercent%28 for helping with this
  
  /assign
  