[alertmanager] Fixing "cannot overwrite table with non table" warning (…

…prometheus-community#3245)

* Fixing "cannot overwrite table with non table" warning

Signed-off-by: Aaron Layfield <[email protected]>

* Correct type at dnsConfig

Signed-off-by: zeritti <[email protected]>

* Update Chart.yaml

Signed-off-by: Quentin Bisson <[email protected]>

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Signed-off-by: Aaron Layfield <[email protected]>
Signed-off-by: zeritti <[email protected]>
Signed-off-by: Quentin Bisson <[email protected]>
Signed-off-by: Quentin Bisson <[email protected]>
Co-authored-by: zeritti <[email protected]>
Co-authored-by: Quentin Bisson <[email protected]>
Co-authored-by: Quentin Bisson <[email protected]>
Co-authored-by: André Bauer <[email protected]>