Introduce TSDB service (#31520)

* Introduce TSDB service

Signed-off-by: Arve Knudsen <arve.knudsen@gmail.com>

Co-authored-by: Erik Sundell <erik.sundell87@gmail.com>
Co-authored-by: Will Browne <will.browne@grafana.com>
Co-authored-by: Torkel Ödegaard <torkel@grafana.org>
Co-authored-by: Will Browne <wbrowne@users.noreply.github.com>
Co-authored-by: Zoltán Bedi <zoltan.bedi@gmail.com>

pkg/plugins/manager/testdata/lacking-files/plugin/MANIFEST.txt

@@ -0,0 +1,24 @@
+
+-----BEGIN PGP SIGNED MESSAGE-----
+Hash: SHA512
+
+{
+  "plugin": "test",
+  "version": "1.0.0",
+  "files": {
+    "executable": "e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855",
+    "plugin.json": "f19e18ca5dec690b94f2ff7866372db4bc63f4ff1101ee5d9061b9a6f026f6dd"
+  },
+  "time": 1589270570251,
+  "keyId": "7e4d0c6a708866e7"
+}
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+Version: OpenPGP.js v4.10.1
+Comment: https://openpgpjs.org
+
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