[Bug] Kibana SLO custom_histogram_indicator panics when using `to` and `from`

[marclop]

Describe the bug

module.SLO.elasticstack_kibana_slo.e2e_latency: Creating...
╷
│ Error: Plugin did not respond
│
│   with module.SLO.elasticstack_kibana_slo.e2e_latency,
│   on ../../slo/main.tf line 10, in resource "elasticstack_kibana_slo" "e2e_latency":
│   10: resource "elasticstack_kibana_slo" "e2e_latency" {
│
│ The plugin encountered an error, and failed to respond to the plugin.(*GRPCProvider).ApplyResourceChange call. The plugin logs may contain more details.
╵

Stack trace from the terraform-provider-elasticstack_v0.7.0 plugin:

panic: interface conversion: interface {} is int, not float64

goroutine 38 [running]:
github.com/elastic/terraform-provider-elasticstack/internal/kibana.getOrNilFloat({0x14000782c30?, 0x1052d5305?}, 0x0?)
	github.com/elastic/terraform-provider-elasticstack/internal/kibana/slo.go:444 +0x9c
github.com/elastic/terraform-provider-elasticstack/internal/kibana.getSloFromResourceData(0x14000000001?)
	github.com/elastic/terraform-provider-elasticstack/internal/kibana/slo.go:521 +0xc28
github.com/elastic/terraform-provider-elasticstack/internal/kibana.resourceSloCreate({0x10573ab48, 0x1400055b5c0}, 0x0?, {0x1056a0820, 0x140006262c0})
	github.com/elastic/terraform-provider-elasticstack/internal/kibana/slo.go:611 +0xa0
github.com/hashicorp/terraform-plugin-sdk/v2/helper/schema.(*Resource).create(0x1400039f260, {0x10573ab80, 0x14000300ff0}, 0xd?, {0x1056a0820, 0x140006262c0})
	github.com/hashicorp/terraform-plugin-sdk/v2@v2.26.1/helper/schema/resource.go:707 +0xe8
github.com/hashicorp/terraform-plugin-sdk/v2/helper/schema.(*Resource).Apply(0x1400039f260, {0x10573ab80, 0x14000300ff0}, 0x140000a9110, 0x1400039ac00, {0x1056a0820, 0x140006262c0})
	github.com/hashicorp/terraform-plugin-sdk/v2@v2.26.1/helper/schema/resource.go:837 +0x888
github.com/hashicorp/terraform-plugin-sdk/v2/helper/schema.(*GRPCProviderServer).ApplyResourceChange(0x1400000d368, {0x10573ab80?, 0x14000300ed0?}, 0x14000302370)
	github.com/hashicorp/terraform-plugin-sdk/v2@v2.26.1/helper/schema/grpc_provider.go:1021 +0xb78
github.com/hashicorp/terraform-plugin-mux/tf5muxserver.muxServer.ApplyResourceChange({0x14000381080, 0x140004ad230, 0x140003810b0, 0x140003810e0, {0x1400036f660, 0x1, 0x1}}, {0x10573ab80?, 0x14000300ba0?}, 0x14000302370)
	github.com/hashicorp/terraform-plugin-mux@v0.11.1/tf5muxserver/mux_server_ApplyResourceChange.go:30 +0x100
github.com/hashicorp/terraform-plugin-go/tfprotov5/tf5server.(*server).ApplyResourceChange(0x140002e1360, {0x10573ab80?, 0x140003001b0?}, 0x140005260e0)
	github.com/hashicorp/terraform-plugin-go@v0.17.0/tfprotov5/tf5server/server.go:821 +0x3bc
github.com/hashicorp/terraform-plugin-go/tfprotov5/internal/tfplugin5._Provider_ApplyResourceChange_Handler({0x1056ce860?, 0x140002e1360}, {0x10573ab80, 0x140003001b0}, 0x14000526070, 0x0)
	github.com/hashicorp/terraform-plugin-go@v0.17.0/tfprotov5/internal/tfplugin5/tfplugin5_grpc.pb.go:422 +0x170
google.golang.org/grpc.(*Server).processUnaryRPC(0x1400025e1e0, {0x10573eba0, 0x140003a31e0}, 0x14000308000, 0x1400043ced0, 0x106059020, 0x0)
	google.golang.org/grpc@v1.56.1/server.go:1337 +0xc90
google.golang.org/grpc.(*Server).handleStream(0x1400025e1e0, {0x10573eba0, 0x140003a31e0}, 0x14000308000, 0x0)
	google.golang.org/grpc@v1.56.1/server.go:1714 +0x82c
google.golang.org/grpc.(*Server).serveStreams.func1.1()
	google.golang.org/grpc@v1.56.1/server.go:959 +0x84
created by google.golang.org/grpc.(*Server).serveStreams.func1
	google.golang.org/grpc@v1.56.1/server.go:957 +0x16c

Error: The terraform-provider-elasticstack_v0.7.0 plugin crashed!

This is always indicative of a bug within the plugin. It would be immensely
helpful if you could report the crash with the plugin's maintainers so that it
can be fixed. The output above should help diagnose the issue.

To Reproduce
Steps to reproduce the behavior:

1. TF configuration used '...'
2. TF operations to execute to get the error '...' [e.g terraform plan,terraform apply, terraform destroy]
3. See the error in the output '...'

resource "elasticstack_kibana_slo" "processing_slo" {
  name             = "[MIS] E2E latency SLO"
  description      = "Proportion of valid events that are processed in under 3 minutes"
  budgeting_method = "occurrences"
  timestamp_field  = "@timestamp"

  histogram_custom_indicator {
    index = "metrics-*"
    good {
      field       = "event.latency"
      aggregation = "range"
      from        = 0
      to          = 180
    }
    total {
      field       = "event.latency"
      aggregation = "value_count"
    }
    
  }

  time_window {
    duration = "30d"
    type     = "rolling"
  }

  objective {
    target = 0.99
  }
}

Expected behavior
A clear and concise description of what you expected to happen.

Debug output
Run terraform command with TF_LOG=trace and provide extended information on TF operations.

Screenshots
If applicable, add screenshots to help explain your problem.

Versions (please complete the following information):

• OS: [e.g. Linux]
• Terraform Version [e.g. 1.0.0]
• Provider version [e.g. v0.1.0]
• Elasticsearch Version [e.g. 7.16.0]

Additional context
Add any other context about the problem here.