support legacy kv engine of type generic

[guillier]

engine type error was partly fixed with issue #232 but still remains a problem with export.

vkv export -p generic_se/path
panic: interface conversion: interface {} is nil, not map[string]interface {}

goroutine 1 [running]:
github.com/FalcoSuessgott/vkv/pkg/vault.(*Vault).GetEngineTypeVersion(0xc000354948?, {0xc000354948, 0x3})
	/home/runner/work/vkv/vkv/pkg/vault/engine.go:55 +0x228
github.com/FalcoSuessgott/vkv/pkg/printer/secret.(*Printer).printBase(0xc0003da0a0, 0xc0004d8b70?)
	/home/runner/work/vkv/vkv/pkg/printer/secret/base.go:36 +0x377
github.com/FalcoSuessgott/vkv/pkg/printer/secret.(*Printer).Out(0xc0003da0a0, {0xae16a0?, 0xc0004d87b0?})
	/home/runner/work/vkv/vkv/pkg/printer/secret/secret_printer.go:224 +0x2ac
github.com/FalcoSuessgott/vkv/cmd.NewExportCmd.func1(0xc0004b6200?, {0xc00061f460?, 0x4?, 0xb99cfc?})
	/home/runner/work/vkv/vkv/cmd/export.go:84 +0x594
github.com/spf13/cobra.(*Command).execute(0xc0004a7b00, {0xc00061f440, 0x2, 0x2})
	/home/runner/go/pkg/mod/github.com/spf13/[email protected]/command.go:985 +0xabc
github.com/spf13/cobra.(*Command).ExecuteC(0xc0004a7800)
	/home/runner/go/pkg/mod/github.com/spf13/[email protected]/command.go:1117 +0x3ff
github.com/spf13/cobra.(*Command).Execute(...)
	/home/runner/go/pkg/mod/github.com/spf13/[email protected]/command.go:1041
github.com/FalcoSuessgott/vkv/cmd.Execute()
	/home/runner/work/vkv/vkv/cmd/root.go:117 +0x18
main.main()
	/home/runner/work/vkv/vkv/main.go:15 +0x4f

With the fix:

vkv export -p generic_se/path
generic_se/ [type=kv1]
└── path
...

[codecov]

Codecov Report

Attention: Patch coverage is 0% with 3 lines in your changes missing coverage. Please review.

Project coverage is 69.66%. Comparing base (6b528bc) to head (e47a404).
Report is 124 commits behind head on master.

Files with missing lines	Patch %	Lines
pkg/vault/engine.go	0.00%	2 Missing and 1 partial ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master     #308      +/-   ##
==========================================
+ Coverage   69.59%   69.66%   +0.06%     
==========================================
  Files          29       35       +6     
  Lines        1322     2126     +804     
==========================================
+ Hits          920     1481     +561     
- Misses        290      503     +213     
- Partials      112      142      +30     

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[FalcoSuessgott]

Will fix the tests later. Thanks for the fix! You might wanna consider vkv exporting -> importing to a KVv2 engine :D