Fix backwards compatibility with block version 1 (#802)

This also adds a Test for block version compatibility.

Author: simonswine

pkg/phlaredb/block/testdata/01GR3QABQB6J30Q04K4E6MAKRE/functions.parquet

@@ -0,0 +1,71 @@
+{
+	"ulid": "01GR3QABQB6J30Q04K4E6MAKRE",
+	"minTime": 1675162365.672,
+	"maxTime": 1675162365.672,
+	"stats": {
+		"numSamples": 40,
+		"numSeries": 2,
+		"numProfiles": 2
+	},
+	"files": [
+		{
+			"relPath": "functions.parquet",
+			"sizeBytes": 4918,
+			"parquet": {
+				"numRowGroups": 1,
+				"numRows": 101
+			}
+		},
+		{
+			"relPath": "index.tsdb",
+			"sizeBytes": 1299,
+			"tsdb": {
+				"numSeries": 2
+			}
+		},
+		{
+			"relPath": "locations.parquet",
+			"sizeBytes": 5600,
+			"parquet": {
+				"numRowGroups": 1,
+				"numRows": 108
+			}
+		},
+		{
+			"relPath": "mappings.parquet",
+			"sizeBytes": 1863,
+			"parquet": {
+				"numRowGroups": 1,
+				"numRows": 6
+			}
+		},
+		{
+			"relPath": "profiles.parquet",
+			"sizeBytes": 3171,
+			"parquet": {
+				"numRowGroups": 1,
+				"numRows": 2
+			}
+		},
+		{
+			"relPath": "stacktraces.parquet",
+			"sizeBytes": 945,
+			"parquet": {
+				"numRowGroups": 1,
+				"numRows": 24
+			}
+		},
+		{
+			"relPath": "strings.parquet",
+			"sizeBytes": 9926,
+			"parquet": {
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+				"numRows": 167
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+		}
+	],
+	"compaction": {
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+	"version": 1
+}