Bump deltalake-python version to 0.7.0 (#1098)

# Description

In preparation for new release.

# Related Issue(s)
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- closes #106
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# Documentation

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python/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "deltalake-python"
-version = "0.6.4"
+version = "0.7.0"
 authors = ["Qingping Hou <dave2008713@gmail.com>"]
 homepage = "https://github.com/delta-io/delta-rs"
 license = "Apache-2.0"