Fix SpringBootEnvProvider throws unhandled exception

[hananiel]

Description

The placeholder resolver loads configuration multiple times by design. The SpringBootEnvProvider inherits eventually from StreamConfigurationProvider that does not allow multiple reloads of configuration.

Fixes #1169

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[hananiel]

/azp run Steeltoe.All

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0 Bugs
0 Vulnerabilities
0 Security Hotspots
1 Code Smell

100.0% Coverage
0.0% Duplication