Make sure sys.modules["__main__"] is the module being run by -m

[itamarst]

Fixes #202

[github-actions]

Benchmark results

diff --git a/benchmarks/results/lots-of-peaks.json b/benchmarks/results/lots-of-peaks.json
index a96ee9b..0ecb48f 100644
--- a/benchmarks/results/lots-of-peaks.json
+++ b/benchmarks/results/lots-of-peaks.json
@@ -1,12 +1,12 @@
{
    "D1mr": [-3655149,-]{+3681445,+}
    "D1mw": [-2713965,-]{+2782596,+}
    "DLmr": [-1452624,-]{+1544529,+}
    "DLmw": [-1779154,-]{+1860367,+}
    "Dr": [-229508709,-]{+230386162,+}
    "Dw": [-93311599,-]{+92908961,+}
    "I1mr": [-4106758,-]{+3802018,+}
    "ILmr": [-14565,-]{+15847,+}
    "Ir": [-866790745,-]{+879781219,+}
    "Overall": [-1328904831-]{+1346762868+}
}
diff --git a/benchmarks/results/multithreading-1.json b/benchmarks/results/multithreading-1.json
index e61801c..a71f379 100644
--- a/benchmarks/results/multithreading-1.json
+++ b/benchmarks/results/multithreading-1.json
@@ -1,12 +1,12 @@
{
    "D1mr": [-1820859,-]{+1848180,+}
    "D1mw": [-386474,-]{+396250,+}
    "DLmr": [-60435,-]{+57473,+}
    "DLmw": [-78194,-]{+77723,+}
    "Dr": [-77751713,-]{+73478157,+}
    "Dw": [-32292276,-]{+30226520,+}
    "I1mr": [-1495362,-]{+1622000,+}
    "ILmr": [-8373,-]{+8957,+}
    "Ir": [-257981761,-]{+244194705,+}
    "Overall": [-387246590-]{+367689692+}
}
diff --git a/benchmarks/results/pystone.json b/benchmarks/results/pystone.json
index c0224e2..b34cfe6 100644
--- a/benchmarks/results/pystone.json
+++ b/benchmarks/results/pystone.json
@@ -1,12 +1,12 @@
{
    "D1mr": [-3493431,-]{+5375874,+}
    "D1mw": [-1170982,-]{+1440719,+}
    "DLmr": [-27810,-]{+32670,+}
    "DLmw": [-55475,-]{+66578,+}
    "Dr": [-360208809,-]{+368217613,+}
    "Dw": [-152234419,-]{+154097366,+}
    "I1mr": [-8048210,-]{+10115999,+}
    "ILmr": [-8271,-]{+8846,+}
    "Ir": [-1136235757,-]{+1174637053,+}
    "Overall": [-1702276157-]{+1767925220+}
}
diff --git a/benchmarks/results/version.txt b/benchmarks/results/version.txt
index 30019eb..0c66f42 100644
--- a/benchmarks/results/version.txt
+++ b/benchmarks/results/version.txt
@@ -1 +1 @@
[-2021.5.1.dev10+g128d75e.d20210518-]{+2021.7.2.dev7+gc6fc06d.d20210814+}