ASM-15848 | Fix Panic Reading Static Secret

[kgal-akl]

Fix plugin crashing when attempting to read static secret:

Stack trace from the terraform-provider-akeyless_v1.11.0 plugin:

panic: interface conversion: interface {} is nil, not string

goroutine 39 [running]:
github.com/akeylesslabs/terraform-provider-akeyless/akeyless.dataSourceStaticSecretRead(0xc00070c510, {0x1b69780?, 0xc0006c0530})
	github.com/akeylesslabs/terraform-provider-akeyless/akeyless/data_source_static_secret.go:91 +0xaf3
github.com/akeylesslabs/terraform-provider-akeyless/akeyless.dataSourceSecretRead(0xc00070c510, {0x1b69780, 0xc0006c0530})
	github.com/akeylesslabs/terraform-provider-akeyless/akeyless/data_source_secret.go:63 +0x2c5
github.com/hashicorp/terraform-plugin-sdk/v2/helper/schema.(*Resource).read(0x230f8a0?, {0x230f8a0?, 0xc0006e8ea0?}, 0xd?, {0x1b69780?, 0xc0006c0530?})
	github.com/hashicorp/terraform-plugin-sdk/v2@v2.37.0/helper/schema/resource.go:854 +0x15f
github.com/hashicorp/terraform-plugin-sdk/v2/helper/schema.(*Resource).ReadDataApply(0xc0005b4a00, {0x230f8a0, 0xc0006e8ea0}, 0x0?, {0x1b69780, 0xc0006c0530})
	github.com/hashicorp/terraform-plugin-sdk/v2@v2.37.0/helper/schema/resource.go:1088 +0x13e
github.com/hashicorp/terraform-plugin-sdk/v2/helper/schema.(*GRPCProviderServer).ReadDataSource(0xc0005420a8, {0x230f8a0?, 0xc0006e8de0?}, 0xc0006e8d80)
	github.com/hashicorp/terraform-plugin-sdk/v2@v2.37.0/helper/schema/grpc_provider.go:1860 +0x6ac
github.com/hashicorp/terraform-plugin-go/tfprotov5/tf5server.(*server).ReadDataSource(0xc000463400, {0x230f8a0?, 0xc0006e82d0?}, 0xc000693860)
	github.com/hashicorp/terraform-plugin-go@v0.27.0/tfprotov5/tf5server/server.go:757 +0x26a
github.com/hashicorp/terraform-plugin-go/tfprotov5/internal/tfplugin5._Provider_ReadDataSource_Handler({0x1e8f080, 0xc000463400}, {0x230f8a0, 0xc0006e82d0}, 0xc000440200, 0x0)
	github.com/hashicorp/terraform-plugin-go@v0.27.0/tfprotov5/internal/tfplugin5/tfplugin5_grpc.pb.go:741 +0x1a9
google.golang.org/grpc.(*Server).processUnaryRPC(0xc0003aa000, {0x230f8a0, 0xc0006e8240}, 0xc00068dd40, 0xc000549ec0, 0x3587b30, 0x0)
	google.golang.org/grpc@v1.73.0/server.go:1405 +0x1036
google.golang.org/grpc.(*Server).handleStream(0xc0003aa000, {0x2310430, 0xc0005c4340}, 0xc00068dd40)
	google.golang.org/grpc@v1.73.0/server.go:1815 +0xb88
google.golang.org/grpc.(*Server).serveStreams.func2.1()
	google.golang.org/grpc@v1.73.0/server.go:1035 +0x7f
created by google.golang.org/grpc.(*Server).serveStreams.func2 in goroutine 18
	google.golang.org/grpc@v1.73.0/server.go:1046 +0x11d

Error: The terraform-provider-akeyless_v1.11.0 plugin crashed!

[tuvia-akeyless]

The data source secret in this file handles static + dynamic + rotated secrets. But the gateway supports ignore_cache param only for static and rotated secrets. I will do another pr.

[kgal-akl]

Closed for #152